FLAFS 2023 Abstracts

Presenter Last Name

Changes in Piney Z Lake Productivity and Ecosystem Biodiversity due to contaminants.

Presenter: Jenny Allume *
Institution:
Coauthors:
Omolola Betiku |
Lekan Latinwo |
Eriola Betiku |
Andy Strickland |
Abstract:
Lakes play significant roles in the immediate community by providing unique benefits such as the provision of water, aid in climate regulation and ecological balance, and provision to the human population. Anthropogenic activities and natural factors can impact lake ecosystems’ water quality, influencing their biogeochemical cycles. Lake Piney Z is a 240-acre community lake located in Tallahassee, Florida, that is utilized for fishing. Lake water contamination by pathogens and heavy metals is a major public health issue due to its devastating effect on humans and animals, whose lives depend on it for sustenance. According to the Environmental Protection Agency (EPA), elevated levels of pathogens cause impairments to coastal water and the immediate environment. This study aims to characterize the pathogenic microorganisms in Piney Z Lake while evaluating the concentration of certain metals on how they affect the microbial diversity in the aquatic ecosystem. Piney Z Lakes was divided into five subsections, and we collected samples of water, sediments, and water from each section. Largemouth Bass and Bluegill are fish sampled for intestinal content and tissue. We determined the physiochemical properties of each lake section before each sampling. The results indicated that water temperature ranges between 22.1 C and 22.9 C and 19.7 C and 22.9 C for the two sampling periods, from November to December. Average water conductivity of 32 uS/cm and 31.5 uS/cm were reported for November and December, respectively. Largemouth bass had a higher weight than Bluegill, with weight ranges from 35 -1995 g and 31 – 178 g in Bluegill for both sampling periods. Laboratory analyses of sediments and water samples for organic nutrients and heavy metal determination; and digestive tissue and contents for digestive enzymes and microbiome analyses are ongoing. Data and results obtained following these laboratory analyses will be presented at the conference.


Assessing effects of Tilapia Oreochromis spp. on Largemouth Bass Micropterus salmoides and Bluegill Lepomis macrochirus reproduction, recruitment, and growth

Presenter: Chris Anderson He/Him/His *
Institution: 1Florida Fish and Wildlife Conservation Commission
Fish and Wildlife Research Institute
Freshwater Fisheries Research
2University of Florida
Florida Cooperative Fish and Wildlife Research Unit
School of Forest
Fisheries
and Geomatics Sciences
Coauthors:
Andrew Carlson | University of Florida, Florida Cooperative Fish and Wildlife Research Unit, School of Forest, Fisheries, and Geomatics Sciences and Department of Wildlife Ecology and Conservation
Abstract:
Quantitative research evaluating the effects of non-native freshwater fishes on native species in Florida is lacking despite the importance of this information for management. To address this knowledge gap, we will conduct a pond study evaluating the effects of one of the most widespread genera of non-native freshwater fish, Tilapia Oreochromis spp. (Oreochromis aureus, Oreochromis niloticus, and their hybrids; hereafter referred to as Tilapia), on two ecologically and socioeconomically important native fishes, Largemouth Bass Micropterus salmoides and Bluegill Lepomis macrochirus. Introduced in the 1960s, Tilapia have become widely established throughout peninsular Florida. Previous experimental research on the effects of high densities of Blue Tilapia Oreochromis aureus on Largemouth Bass has demonstrated reduced age-0 production, recruitment, and growth. However, these studies were limited in that they only evaluated the effects of high densities of Blue Tilapia on age-0 LMB production and growth. We aim to build on these studies by evaluating the effects of both low and high density Tilapia populations on age-0 and age-1 Largemouth Bass and Bluegill reproduction, recruitment, and growth in 0.4-ha ponds (n = 9). The study site (USGS Wetland and Aquatic Research Center in Gainesville, FL) is located near the current latitudinal limit of established Tilapia populations in Florida, which makes it an opportune location to study interactions of Tilapia with Largemouth Bass and Bluegill given possible Tilapia range expansion and/or population growth in north central Florida and the panhandle due to climate change.


Sex and Size Distribution of Blacktip Sharks in Southeast Florida

Presenter: Savannah Arvin She/Her *
Institution: Elasmobranch Lab at Florida Atlantic University
Coauthors:
Stephen Kajiura | Head of Elasmobranch at FAU
Abstract:
The Blacktip Shark (Carcharhinus limbatus) is a common species of large coastal shark found throughout the United States eastern seaboard from Florida to New York. This species has a well-established migratory pattern and overwinters in Southeast Florida from about January to March. During these months the sharks form large aggregations in the nearshore environment where they are targeted in a shore-based recreational fishery. Since 2014, researchers at Florida Atlantic University have undertaken targeted fishing for blacktips within 200m of the beach in Palm Beach County, Florida. Significantly greater fishing effort was expended during the winter months (January to March) when sharks are in greatest abundance, with only sporadic fishing at other times of the year. From these efforts, a total of 201 blacktip sharks were caught, of which 190 (94.5%) were male and 11 (5.5%) were female. Females ranged from 146 cm to 186 cm, with a mean of 167.6cm. Males ranged from 145 cm to 188 cm TL, with a mean of 171.0 cm. Clasper length and calcification indicated that all males caught were sexually mature. Sharks were captured from 26°24’09.6” latitude to 26°85’41.8” latitude with greater fishing effort north of the Palm Beach Inlet. These data help to inform us about the size and sex distribution of the blacktip shark aggregations at the southern terminus of their migration. It appears that the males migrate farther south and dominate the sex distribution with females remaining at higher latitudes and only rarely occurring in the large aggregations. This information is important for the recreational fishery that targets the aggregated sharks and may be selectively catching adult males. This may contribute to a healthy shark population which supports both a recreational and commercial fishery for this species.


A hedonic analysis of ex-vessel spiny lobster prices in Florida

Presenter: Frank Asche
Institution: University of Florida
Coauthors:
Taryn Garlock | School of Forest, Fisheries, and Geomatic Sciences, University of Florida
Abstract:
Spiny lobster is one of Florida’s most important commercial fisheries with a value of $42 million. The economic viability of the Florida spiny lobster fishery is inextricably linked to exports of spiny lobster to China. China is the major market for frozen and live spiny lobster, the two major product forms, with about 70% of frozen exports and about 90% of live exports of spiny lobster going to China each year. Live lobster is much more valuable than frozen as the price of live lobster is nearly double the price of frozen lobster. Thus, the live export market potentially provides an economic opportunity to enhance the value of the fishery. However, the market potential may be limited by the seasonal landing pattern. We estimate a hedonic price function to estimate the effects of product characteristics and seasonality on the ex-vessel price of lobster. The hedonic analysis is conducted on ex-vessel data from 2010 to 2022 collected by the Florida Fish and Wildlife Conservation Commission’s Commercial Trip Ticket Program. The results show there is potential to increase the revenue of the fishery if spiny lobster can be landed live and later in the season with the highest premiums in the months of January and February. This provides a significant incentive for live storage and on-growth of spiny lobster.


Reproductive activity of Shoal Bass in hatchery ponds

Presenter: Brandon Barthel
Institution: Florida Fish and Wildlife Conservation Commission
Coauthors:
Andy Strickland | Florida Fish and Wildlife Conservation Commission
Bob DeMauro | Florida Fish and Wildlife Conservation Commission
Bryan Winston | Florida Fish and Wildlife Conservation Commission
Ryan Henry | Florida Fish and Wildlife Conservation Commission
Abstract:
The Shoal Bass is a black bass species that is native to the Apalachicola-Chattahoochee-Flint River system in Florida, Georgia, and Alabama. The sole Shoal Bass population in Florida is restricted to a 48 km stretch of the Chipola River, where it has been impacted by habitat disturbance and introgression with congeners. The Florida Fish and Wildlife Conservation Commission recognizes the value of Chipola River Shoal Bass both as an angling resource and as a unique part of the biodiversity of Florida. Supportive breeding and stocking have been identified as potential conservation actions if the population’s persistence was to become seriously threatened. To this end, adult Shoal Bass have been collected from the Chipola River and placed in ponds at the Blackwater Fisheries Research Center for spawning trials in a number of years. These trials were intended to evaluate whether this lotic species would successfully spawn under the lentic conditions in the hatchery ponds. Genetic techniques were used to identify the adults that produced a subsample of young-of-the-year offspring collected from the ponds. Genetic coparentage analyses linked offspring to their parents and provided information on parental contributions and reproductive dynamics. Reproductive activity was remarkably similar in the two successful years of spawning. Ten adult Shoal Bass were found to have contributed offspring in each of the two years. Many of these fish were found to have spawned with multiple partners in a single year, resulting in 8 and 9 mating pairs in the two cycles. The most successful pairs produced 40% of the sampled offspring in each year and the effective breeding size estimates were nearly identical. This spawning information can be used to predict potential genetic impacts of stocking and provides managers with information they can use to modify breeding protocols to meet parental contribution objectives.


Engaging stakeholders in the management of the Orange Creek Basin in north central Florida

Presenter: Steve Beck
Institution: Florida Fish and Wildlife Conservation Commission/Division of Freshwater Fisheries Management
Abstract:
The Orange Creek Basin (OCB) includes three major lakes: Orange, Lochloosa, and Newnans lakes. Past and ongoing management and stakeholder communication strategies for this system will be discussed, including the development of two key documents: The Fish and Wildlife Habitat Guidelines for the Aquatic Resources of the OCB (2007), and the Orange Lake Habitat Management Plan (2016). The former was developed to provide scientific recommendations to balance habitat needs across focal taxa, and the latter was developed with extensive input from members of the public to balance the interests of diverse user groups. FWC continues to cooperatively manage this system based on regular monitoring and maintains regular intra-agency, inter-agency, and public communication. These efforts ensure stakeholder awareness of current conditions, concerns, and future management decisions.


A Year in the Life of Alligator Gar in Pensacola Bay

Presenter: Calvin Beech
Institution: Florida Fish and Wildlife Conservation Commission
Coauthors:
Amanda Mattair | Florida Fish and Wildlife Conservation Commission
Matt Wegener | Florida Fish and Wildlife Conservation Commission
Abstract:
Alligator Gar Atractosteus spatula are large riverine fish that can grow to around 150kg and range across the southeastern U.S. In Florida, Alligator Gar are only found within Gulf Coastal rivers west of the Apalachicola River and are considered rare. Alligator Gar populations throughout their range have historically been declining or absent since the mid 1900’s. Recognizing this decline and the need for conservation, Florida Fish and Wildlife (FWC) closed harvest of Alligator Gar in Florida waters in 2006 to anyone without a special permit. Abundance estimates are needed to determine if the harvest closure is necessary. A population estimate conducted on the Escambia River in 2014-2015, indicated additional research was needed throughout the range of Alligator Gar in Florida to complete this evaluation. While few individuals have been caught in the Pensacola Bay system since 2016 (n <10), recent genetic and telemetry data suggest that the Escambia River could be the source population for all of Pensacola Bay. The objectives of this study were to (1) use telemetry to determine movement of tagged fish in Pensacola Bay and (2) locate when and where Alligator Gar aggregate in Escambia Bay for future population estimates. Research from this study will help inform managers better understand Alligator Gar population dynamics across their Florida range.


Movement patterns and habitat use of young-of-the-year scalloped hammerhead sharks (Sphyrna lewini) in the Tolomato river nursery

Presenter: Matthew Bernanke He/Him *
Institution: University of North Florida
Coauthors:
Jim Gelsleichter | University of North Florida
Abstract:
Recently, we have determined that portions of the Atlantic Intracoastal Waterway in the Tolomato River, FL serve as a nursery habitat for young-of-the-year (YOY) scalloped hammerheads Sphyrna lewini. The goal of this study is to determine the extent of nursery habitat use by YOY S. lewini in this system. Our objectives are to determine the temporal and spatial ranges of YOY S. lewini within the nursery and the factors that drive fine scale movement and habitat use, as well as understand how YOY S. lewini use food resources of the system in conjunction with other species. We will address these questions using several methods. Active acoustic telemetry will allow us to evaluate the factors that drive YOY S. lewini shark movement/habitat use throughout the nursery, as well as the fine-scale spatial range for these sharks. Passive acoustic telemetry will inform us of the distinct temporal range of these sharks, their broad scale movement patterns within the nursery, and provide data on emigration from the system. Stable isotope analysis will help us determine if resource partitioning is occurring between YOY S. lewini and other elasmobranchs utilizing the system. Preliminary data for habitat use show little significance of environmental factors, but potential influence of predation and food availability. Additionally, the expansion of home range and activity space that occurs throughout the summer appears consistent with the literature.


Hooked On Apopka: Partnering with a citizens group to combat the Dead Lake Stigma

Presenter: Scott Bisping
Institution: Florida Fish and Wildlife Conservation Commission
Coauthors:
Brandon Thompson | Florida Fish and Wildlife Conservation Commission
Abstract:
In the early 1900s, Lake Apopka was a world-class bass fishing destination. Poor water quality and habitat degradation led to a collapse of the fishery. The state of Florida focused attention on restoring Lake Apopka through multiple agencies and legislative actions. Even though large-scale restoration projects led to improved habitat and more abundant sportfish in parts of the lake, fishing effort remained extremely low and continued to have a reputation of being a “Dead Lake”. Fisheries managers utilized an innovative strategy to promote the fishery at Lake Apopka and the restoration activities through incentivizing anglers to fish. The Florida Fish and Wildlife Conservation Commission (FWC) partnered with The Friends of Lake Apopka (a citizen advocacy group focused on restoring Lake Apopka) to initiate a Lake Apopka fishing challenge. The goal of the contest was to get anglers on the lake to experience the fishing opportunities at Lake Apopka, to help overcome the “dead lake stigma” and eventually increase angler effort. The contest ran from January 15th through May 31st, 2021, where 500 sportfish (i.e., Bass, Black Crappie and Bluegill) were tagged with over $10,000 in rewards up for grabs, including a trophy largemouth bass that was worth up to $5,000. Many sponsors were on board to help fund the contest, including FWC’s TrophyCatch program. The fishing challenge was heavily promoted through various media outlets, and managers took the opportunity to not only promote the contest, but the many restorations projects (e.g., bass stocking, fish attractors, and replanting efforts), and FWC’s monitoring and research programs. Biologists evaluated the success of the contest by monitoring trends in angler effort through game cameras at all public access points. A human dimension survey was also used to evaluate angler opinions and attitudes regarding the contest and Lake Apopka. Managers were interested if this fishing challenge would significantly increase angling effort, but ultimately, the goal would be for anglers to appreciate the underutilized fishery and any elevated effort would continue long-term.


Artificial reef fish monitoring on a citizen science-based program in Taylor County, Florida

Presenter: Victor Blanco
Institution: Florida Sea Grant – Taylor County UF/IFAS Extension
Abstract:
Taylor County have been deploying artificial reef materials to create an artificial reef at Buckeye, located 22 miles offshore East of Steinhatchee, Gulf of Mexico. As it has become a popular fishing spot, it is necessary to describe the fish structure associated to the artificial reefs and assess the structures. Grant funds from FWC were allocated to perform the Buckeye Reef Monitoring Program. A Social media campaign helped enroll volunteer divers to support the efforts on a Citizen Science-based program. The divers training session, including an online module for fish identification, and an in-person training for fish census, artificial reef structure assessment and fish identification methods was held annually since 2018. A total of 60 volunteer divers have been trained. The goal was to collect valid scientific data over fish population and artificial reef structures at eighteen (in 2018) and six (in 2021) different deployment sites at Buckeye Reef to promote this location for recreational fishing and diving, and to evaluate the impact of the county reef program. During the 2018-2022 period volunteer divers invested 1,680 hours, of which 165 are diving hours, equivalent to $37K in contributions. Fish data documented 31 species of 19 families for the stationary count method. For roving dive counts, a total of 37 species of 25 families were recorded. Gag groupers and Amberjacks represent the largest abundant fish in the Sportfish group, followed by Hogfish, Red grouper, Barracudas, Sheepshead, Red Snapper, and Gray triggerfish. No Lionfish has been recorded during the monitoring program. Fish have a relative higher abundance in scrap metal, followed by tetrahedrons, culverts, and concrete cubes, respectively, mainly due to material’s footprint and structure age. In average, 98% of the reef material is intact with incrusting algae, sponges and anthozoans as predominant coverage species. The bottom coverage of reef materials assessed is 5,576 sqft (scrap metal accounts for 75%).


An analysis of the feeding ecology of invasives and native species in the Everglades

Presenter: Tala Bleau she/her *
Institution: University of Tampa
Coauthors:
Bridgette Froeschke | University of Tampa
Abstract:
Cichlids have been invading Florida since the 1940s and the extent of their impacts on the feeding ecology of native species has not been fully described. The percent stomach content of Mayan Cichlids, Oscars, and Tilapia from the Everglades was determined. Percent stomach content was also determined for natives in the Everglades, including Rockbass, Warmouth, Bluegill, Spotted Sunfish, and Redear Sunfish. An Analysis of Similarities (ANOSIM) showed a significant difference between invasive and native feeding niches. A Multidimensional Scaling (MDS) analysis confirmed this difference between invasive and native feeding niches with little overlap between the two groups. An ANOSIM between all species also showed a significant difference between individual feeding niches. Comparison of individual species through MDS analysis indicated similar feeding niches between Oscars and Warmouth, Bluegill and Spotted Tilapia, and no overlap between Mayan Cichlids and Bluegill. A large portion of the Mayan Cichlid feeding niche had no overlap with any other fish. More specifically, the diet of Mayan Cichlids was comprised of 37.08% gastropods, 22.08% fish, 13.79% insect, 9.46% detritus, 7.19% shrimp, 4.25% algae, 3.62% nematodes, 1.93% seagrass, and 0.59% crab. The Oscar’s diet consisted of 32.77% fish, 25.46% shell, 19.39% crayfish, 17.84% insect, 2.45% algae, 1.37% nematodes, 0.72% detritus. Tilapia were found to have 100% algae in their stomachs. This research is crucial because the information can be used to observe what impact invasive cichlids have on native species in the Everglades and what resources have the potential to be depleted as cichlids continue to spread and occupy habitats of natives.


Age, Growth, and Maturity of American Eel in the Lower St. Johns River, Florida

Presenter: Kimberly Bonvechio she/her
Institution: Florida Fish and Wildlife Conservation Commission
Coauthors:
Trevor Phillips | Florida Fish and Wildlife Conservation Commission
Michelle Taliercio | South Carolina Department of Natural Resources
Brittany Bottom | Florida Fish and Wildlife Conservation Commission
Abstract:
The American Eel Anguilla rostrata stock is in a state of decline with the species facing a myriad of threats from across its large geographic range. There is a paucity of information about American Eel populations in much of its range, including Florida. This study aims to collect important life history and population dynamics data for the lower St. Johns River eel population, the first study of its kind in Florida. During a twelve-week period from August to November 2021 and September to December 2022, eels were collected from ~90 rkm via boat electrofishing. Catch rates were low with only 297 eels collected to date despite more than 63.5 hrs of sampling effort. Overall, fish ranged in size from 150 to 705 mm TL and were primarily collected in the lowest reach of the river in shallow (< 1-m) habitats containing riprap, woody snag, and emergent vegetation. Adult Anguillicoloides crassus parasites were observed in 36% of individuals, and 57% exhibited some level of damaged swimbladder as indicated by non-zero swimbladder degenerative index (SDI) scores. No differences in length-weight relationships were observed between fish with impacted or unimpacted swimbladders or those with or without active infections. Fish samples are currently still being processed, but histological examination of gonads from 87 eels collected in 2021 revealed most were immature females or undifferentiated and 2021 age data revealed fish up to age 8 yrs old in the sample. Additional sex, gonad staging, and age data will provide critical inputs for describing the sex-specific growth rate and maturity of eels in the St. Johns River.


Ageing methodology of American Eel Anguilla rostrata in Florida

Presenter: Brittany Bottom
Institution: Florida Fish and Wildlife Conservation Commission
Coauthors:
Jessica Carroll | Florida Fish and Wildlife Conservation Commission
Kimberly Bonvechio | Florida Fish and Wildlife Conservation Commission
Abstract:
The American Eel Anguilla rostrata is a catadromous fish species found along the Atlantic coast from Greenland to Venezuela. Because of its wide range, a variety fisheries laboratories have a stake in researching this species. While otoliths are the accepted ageing structure for American Eel, the methodology of processing these structures varies between laboratory, and no standardized otolith processing protocol has been established across its range. Florida Fish and Wildlife Research Institute’s Age and Growth Lab has been in existence since the 1990s and processes on average 30,000 otoliths per year from approximately 70 different species of fish. Prior to 2018, no American Eel sampling program existed in the state of Florida. However, since sampling of the St. Johns River began, FWRI’s ageing lab successfully applied previous processing and ageing experience to eels. The aim of this presentation is to outline Florida’s method of processing American Eel otoliths, highlight eel-specific issues that can arise when processing and ageing, and demonstrate the banding pattern that is common to Florida eel otoliths.


FISHstory – Using Citizen Science to Describe Historic Catches in the U.S. South Atlantic

Presenter: Julia Byrd she/her/hers
Institution: South Atlantic Fishery Management Council
Coauthors:
Chip Collier | South Atlantic Fishery Management Council
Allie Iberle | South Atlantic Fishery Management Council
Abstract:
The U.S. South Atlantic region has many long- standing data needs and limited data collection resources for federally managed marine fish stocks. Much of the harvest is dominated by recreational fisheries, where data are limited, especially during historic time periods. FISHstory, a pilot project developed through the South Atlantic Fishery Management Council ’s Citizen Science Program, developed a standardized protocol for archiving and analyzing historic photos from the 1940s to 1970s from a for- hire fleet based in Daytona Beach, Florida. These photos document the beginnings of the South Atlantic for-hire fishery and provided an untapped source of data to recreate information on catch and length composition before fishery dependent surveys began. FISHstory had three primary components: digitizing and archiving historic fishing photos; analyzing historic photos to estimate for-hire catch composition and effort through the Zooniverse online crowdsourcing platform; and developing a method to estimate fish length in historic photos using lumber in the leaderboards as a scalar. Industry and agency volunteers were involved by sharing fishing photos, informing project development, and/or contributing to data validation. A broader group of citizen scientists helped test the protocol for identifying fish and contributed to data collection from the historic photos. FISHstory was designed to ensure data collected would be fit for purpose and useful to management. This presentation will highlight the deliberate steps taken in the development of the project, share key project results describing how the data collected can be applied to management, and describe lessons learned through project development.


Anglers as an increasingly specialized and diversified predator

Presenter: Edward Camp he/his
Institution: University of Florida
Coauthors:
Zachary Siders | University of Florida
Frank Asche | University of Florida
Kai Lorenzen | University of Florida
Abstract:
Recreational fisheries are recognized as socioecological systems in which anglers act a unique “predator”. The ecosystem effects of fishing depend in large part on what species fisher “predators” try to catch, or target. These decisions should shift as species’ abundance, fishery technology, and angling knowledge change, as has occurred rapidly over the last several decades. However, long-term changes in targeting behaviors have rarely been assessed, especially for large marine systems. Our objective was to assess how targeting behaviors have or have not changed in marine recreational fisheries. We analyzed decades of data describing targeting and catch-and-release behaviors of marine recreational fishers from the U.S. Atlantic and Gulf coast. We found several key trends. In most locations, the proportion of anglers who did not target specific species (e.g., no target species) has decreased over time, suggesting increased average angler specialization. At the same time, the diversity of primarily or secondarily targeted species has increased, indicating a wider range of species specifically targeted. These trends together suggest the angling population may be functioning as an increasingly specialized and diversified predator capable of effectively targeting more species than ever before. Implications for ecosystem-based management of recreational fisheries include an increasing number of species or stocks whose exploitation necessitates assessment and management, as well as the importance of understanding target-switching behavior to anticipate ecosystem ramifications of management changes to one or more species.


Re-crafting oyster management with an understanding of stakeholder’s knowledge and preferences

Presenter: William Casola he/him
Institution: Fisheries and Aquatic Sciences
School of Forest
Fisheries
and Geomatic Sciences
University of Florida
Coauthors:
Darlene Saindon Velez | Fisheries and Aquatic Sciences, School of Forest, Fisheries, and Geomatics Sciences, University of Florida
Elizabeth Pienaar | Warnell School of Forestry and Natural Resources, University of Georgia
Ed Camp | Fisheries and Aquatic Sciences, School of Forest, Fisheries, and Geomatics Sciences, University of Florida
Abstract:
Oysters are a valuable natural resource to coastal Florida. They provide numerous ecosystem services and support local economies through commercial harvest. However, oyster populations are declining, with the most storied fishery, Apalachicola Bay, collapsing in 2012. Oysters critical biological and economic role in coastal systems underscores the need to make good management decisions that sustain them, while the declining population suggest past approaches may need to be revised. To co-develop recommendations for revised oyster fishery management in Suwannee Sound, we used a participatory, place-based management framework paired with a stated-preference survey to explore potential management changes that are palatable to oyster harvesters and likely to lead to ecological and socioeconomic sustainability. We began by organizing working group meetings where oyster harvesters identified the needs and concerns of the industry and developed criteria (e.g., livelihoods, health regulations, resource regulation) for evaluating the various management strategies and regulatory options. Insights learned from the working group allowed for the development of a stated-preference survey that was distributed to the larger oyster harvesting community within the region (Levy, Dixie, Citrus counties). While most oyster harvesters (86%) agree that oyster populations have declined within the region, harvesters were split on the factors driving the decline. A majority believed poor management (59%) was a driving factor but few believed overharvest to be an issue (27%). Our results suggest that most harvesters believe they would be worse off with any management changes compared to the status quo, and that the state agency does not manage the resource with the best science available. We discuss our results in the context of cultural cognition theory, and how the lessons learned through this study may provide opportunities for more resilient oyster management along the entire Gulf Coast.


Estimation of Shell Volume Removed From Two Major Oyster Fisheries in Florida

Presenter: Jamie Casteel
Institution: Florida Fish and Wildlife Conservation Commission
Coauthors:
Jennifer Moore |
Bill Pine |
Tyler Coleman |
Abstract:
Oyster reefs have declined over the last 200 years across North America, including Florida, due to factors including overharvest, shell removal, land use, and water quality. Increasingly, restoration efforts are being made, often by adding durable substrate. This work focuses on developing an understanding of the relationship between shell biomass and live oyster density on natural oyster reefs in Suwannee Sound, Florida, to inform restoration and management of oyster reefs by quantifying the range of substrate on wild oyster reefs and how this relates to live oyster density. To assess the amount of shell removed through harvest each year and how much shell should be added to offset removals, fisheries-dependent landings data were compiled and converted to the number of cubic meters of shell removed in Suwannee Sound and Apalachicola Bay. These removals are compared to the amount of material used in the ongoing restoration of Lone Cabbage Reef in Suwannee Sound. Insight into the amount of shell removed by the commercial fishery can be used to guide management and restoration efforts.


Widespread exposure of pharmaceuticals at concentrations of concern to a subtropical coastal marine fish, bonefish (Albula vulpes)

Presenter: Nicholas Castillo *
Institution: Florida International University
Coauthors:
Jennifer Rehage | Florida International University
Rolando Santos | Florida International University
Ryan James | Florida International University
Ryan Rezek | Coastal Carolina University
Daniel Cerveny | SLU University
Tomas Brodin | SLU University
Jerker Fick | Umea University
Aaron Adams | Bonefish and Tarpon Trust
Ross Boucek | Bonefish and Tarpon Trust
Abstract:
Pharmaceuticals have been acknowledged as an important contaminant of emerging concern with the potential to cause adverse effects in exposed fauna. Most research has focused on temperate freshwater systems; therefore, there is a pressing need to quantify pharmaceutical exposure in sub-tropical coastal marine systems. This study investigates the prevalence of pharmaceutical exposure to a recreational fishery, bonefish (Albula vulpes), and their prey items, in South Florida, USA and evaluates the relative risk of effects. We sampled blood plasma from 93 bonefish across five distinct regions and 154 prey items from 3 regions and analyzed them for 102 commonly prescribed pharmaceuticals. The influence of sampling region, season of collection (within or outside spawning season) and bonefish length on pharmaceutical assemblage, detection frequency, and risk was assessed. To quantify risk, we compared the measured concentrations to a threshold of 1/3rd the human therapeutic plasma concentration (HTPC) for each pharmaceutical. A total of 53 different pharmaceuticals were detected in bonefish and 61 in their prey items, with an average of 7.1 pharmaceuticals per bonefish and 11.2 per prey item, and a maximum of 17 and 24 pharmaceuticals per individual, respectively. Across all bonefish, 52.3% had at least one pharmaceutical exceeding the 1/3rd HTPC threshold of effect, with a maximum of 11 pharmaceuticals exceeding the threshold in an individual. In prey items, 93.3% had at least one pharmaceutical exceeding the 1/3rd HTPC threshold and a maximum of 5 in an individual. The presence of pharmaceutical cocktails at concentrations capable of eliciting an effect is of particular concern considering the potential for unknown interactions and additive effects. For both exposure and risk, region and season were the only significant factors, and no effect was detected for bonefish length. We found that exposure and risk was highest in the most remote sampling region, indicating the ubiquitous nature of pharmaceuticals and that their presence is not limited to urbanized and populous areas. Our results establish pharmaceuticals’ widespread prevalence in subtropical coastal marine ecosystems, exposure and risk to biota, and the ne


Shifting Baselines: Effects of seagrass loss on fish communities in Southwest Florida tidal creeks.

Presenter: Kelly Chase He/His/Him *
Institution: 1) Florida Fish and Wildlife Conservation Commission
Fish and Wildlife Research Institute
Charlotte Harbor Field Lab
585 Prineville St.
Port Charlotte
FL 33954
USA
2)University of Florida
Institute of Food and Agricultural Sciences
Tropical Aquaculture Laboratory
Program in Fisheries and Aquatic Sciences
School of Forest
Fisheries
and Geomatics Sciences
1408 24th Street SE
Ruskin
FL 33570
USA
Coauthors:
David Blewett | Florida Fish and Wildlife Conservation Commission, Fish and Wildlife Research Institute, Charlotte Harbor Field Lab, 585 Prineville St., Port Charlotte, FL 33954, USA
Philip Stevens | Florida Fish and Wildlife Conservation Commission, Fish and Wildlife Research Institute, 100 8th Ave SE, St. Petersburg, FL 33701, USA
Courtney Saari | 1) Florida Fish and Wildlife Conservation Commission, Fish and Wildlife Research Institute, 100 8th Ave SE, St. Petersburg, FL 33701, USA
2) Florida Fish and Wildlife Conservation Commission, Fish and Wildlife Research Institute, Charlotte Harbor Field Lab, 585 Prineville St., Port Charlotte, FL 33954, USA
Quenton Tuckett | University of Florida, Institute of Food and Agricultural Sciences, Tropical Aquaculture Laboratory, Program in Fisheries and Aquatic Sciences, School of Forest, Fisheries, and Geomatics Sciences, 1408 24th Street SE, Ruskin, FL 33570, USA
Jeffrey Hill | University of Florida, Institute of Food and Agricultural Sciences, Tropical Aquaculture Laboratory, Program in Fisheries and Aquatic Sciences, School of Forest, Fisheries, and Geomatics Sciences, 1408 24th Street SE, Ruskin, FL 33570, USA
Abstract:
Ecosystem phase shifts from one steady state (e.g., clear water, seagrass) to another (e.g., phytoplankton blooms, bare substrate) are being documented worldwide. In coastal environments, the external stressors that cause phase shifts are numerous and frequently interact, yet case studies often implicate altered hydrology and increased nutrient input. Tidal creeks may be especially prone to phase shifts because of their position in the landscape which exposes them to the brunt of deleterious effects caused by coastal development. We analyzed an eight-year dataset (2014-2022) acquired by fisheries-independent monitoring using 21.3-m seines in tidal creeks on the Cape Haze peninsula of the Charlotte Harbor estuary, Florida. Multivariate analyses identified a change in fish assemblages that coincided with algal blooms and seagrass loss in a tidal creek downstream of development; these changes did not occur in creeks downstream of more natural habitat. Reductions in benthic species, such as rainwater killifish Lucania parva, were offset by increases in the planktivorous bay anchovy Anchoa mitchilli. The phase shift observed in a tidal creek in need of hydrologic restoration may be a harbinger for seagrass losses that are starting to occur in the open estuary. Interagency coordination will be needed to implement estuary-wide strategies for conservation, mitigation, and restoration.


RESPONSES OF MICROBIAL COMMUNITIES TO HEAVY METAL CONTAMINATIONS IN LAKE TALQUIN

Presenter: Jade Chery she/her *
Institution: Florida A&M University
Coauthors:
Omolola Betiku | Florida A&M University
Abstract:
Contamination of community water with heavy metals is a major public health issue because the high concentration of these contaminants is detrimental to the aquatic ecosystem, humans, and livestock. Mercury (Hg) contamination has been the primary pollutant in Lake Talquin, and the 2021 advisory recommendation by the Florida Department of Health limits the number of fish consumed from the lake. To provide a comprehensive assessment of Hg and other heavy contaminants in the lake, we investigated how season and habitat section (a randomized address within the Lake Talquin perimeter) and conditions influence heavy metal concentrations and how microbial communities respond to these factors. Our current results showed higher and significant differences in the pH (P<0.0001), total Kjeldahl nitrogen (TKN) (P<0.0001), and ammonium hydroxide (NHO4) (P<0.0001) between the upper and lower sections of the lake. Likewise, concentrations of Al (P<0.0001), Mg (P<0.0001), and Fe (P<0.001) are significantly different. Interestingly, Hg concentration differed significantly in Bluegill and largemouth bass tissues (P<0.005). Our study confirms the presence of heavy metal contaminants, particularly Hg, in Lake Talquin. Information about how the contaminants influence the microbiota will be presented.


Recreational Angler Preferences for, and Potential Effort Responses, to Different Red Snapper Management Approaches

Presenter: Lisa Chong she/her *
Institution: University Of Florida
Coauthors:
Elizabeth Pienaar | University of Georgia
Robert Ahrens | Pacific Islands Fisheries Science Center, NOAA
Edward Camp | University of Florida
Abstract:
The red snapper fishery in the Gulf of Mexico has been caught in a spiral of more restrictive regulations and disputed management. Current management measures have failed to reduce angler effort and fishing mortality, owing to derby style fishing. A harvest tag system could be implemented to restrict the number of anglers in the recreational fishery and to limit catch. In 2019/20 we surveyed 766 recreational anglers in Florida to ascertain their preferences for changes to the current regulations, and how they would alter their fishing effort if a harvest tag was implemented. Respondents were heterogeneous in terms of their preferences for harvest tags versus current management approaches, with the majority of respondents preferring to maintain their current effort under the existing management approach of bag, size, and season limits. Respondents who preferred harvest tags indicated that they might increase or decrease fishing effort. Our findings suggest that more stringent regulations using current management approaches will not secure angler satisfaction or reduce fishing pressure on the red snapper stock. Although harvest tags might still result in fish mortality from barotrauma, this approach will allow regulators to better manage the number of anglers in the fishery and to rebuild the stock.


Assessing a newly created fishery using a volunteer angler data program

Presenter: Tyler Steven Coleman *
Institution: Florida Cooperative Fish and Wildlife Research Unit
Department of Wildlife Ecology and Conservation
University of Florida
Coauthors:
Mariaguadalupe Vilchez | Florida Cooperative Fish and Wildlife Research Unit, School of Forest, Fisheries, and Geomatics Sciences and Department of Wildlife Ecology and Conservation, University of Florida
Brandon C. Thompson | Florida Fish and Wildlife Conservation Commission
Andrew K. Carlson | U.S. Geological Survey, Florida Cooperative Fish and Wildlife Research Unit, School of Forest, Fisheries, and Geomatics Sciences and Department of Wildlife Ecology and Conservation, University of Florida
Abstract:
The upper basin of Florida’s longest river—the St. Johns—was leveed and drained for agriculture beginning in the early 1900s, resulting in removal of 62% of the basin’s floodplains by the 1970s. Direct negative impacts on the Indian River Lagoon, St. Johns wildlife, and public water supply ensued, causing the Water Management District (WMD) and partner agencies to implement rehabilitation efforts focused on reestablishing floodplain connectivity. One primary river-floodplain rehabilitation strategy is the creation of water management areas (WMAs). Fellsmere WMA (hereafter FWMA) is a key component of the St. Johns River rehabilitation project. Before constructing FWMA, agencies sought to diversify and enhance habitat that had been simplified by monotypic vegetation and flat topography resulting from agriculture. Between 2011 and 2014, the SJRWMD and Florida Fish and Wildlife Conservation Commission (FWC) invested $1.356 million to modify >800 ha, which created a mosaic of habitats. As WMAs are flooded following construction, newly inundated terrestrial habitats are known to cause trophic upsurge. Trophic upsurge in FWMA, combined with land modifications and the presence of stocked and naturally produced fishes, created optimum conditions for a popular Largemouth Bass Micropterus salmoides fishery. The WMA opened to motorboat angling in August 2020 and has since been named “Jurassic Lake” due to its renowned Largemouth Bass abundance and size structure. We are currently collecting information on angler attitudes and behaviors with FWC. For instance, we are using angler diaries in a volunteer angler data (VAD) program to examine Largemouth Bass catch, effort, size structure, condition, and bait preferences, and compare these variables in treatment and control sections of FWMA. By evaluating if and how habitat modification has impacted the fishery, we will derive insights for fisheries management, emphasizing VAD programs and the benefits they offer compared to traditional fisheries data collection methods.


Unsinkable? Developing optimal release strategies for the Goliath grouper (Epinephelus itajara) relevant to recreational fisheries in Florida

Presenter: Angela Collins she/her/hers
Institution: University of Florida
Coauthors:
Clark Morgan | Harbor Branch Oceanographic Institute, Florida Atlantic University
Michael Sipos | Florida Sea Grant, University of Florida
Ana Zangroniz | Florida Sea Grant, University of Florida
Matthew Ajemian | Harbor Branch Oceanographic Institute, Florida Atlantic University
Abstract:
Although Goliath grouper (Epinephelus itajara) have been protected from harvest in federal waters since 1990, fish are still caught regularly by anglers throughout the state of Florida. While there are some who specifically target Goliath grouper for catch and release, there is an even larger contingent of fishers that incidentally catch Goliath grouper while fishing for other reef fish species. Although sustainable fishing practices are recommended (or required) by management (e.g., heavy tackle to reduce fight time, circle hooks to minimize injuries, and encouragement to vent or descend fish), traditional barotrauma mitigation strategies for Goliath grouper are impractical for most recreational fishermen. Anglers often lack the tools and capacity to safely and effectively vent very large fish, and commercially available descending gear is inadequate for most adult (>1 m TL) Goliath grouper due to their size and the amount of weight necessary to submerge the fish. To address the lack of guidance regarding release of these large reef fishes, we are coordinating with recreational reef fish anglers and charter captains to identify and evaluate the most realistic methods for barotrauma mitigation of Goliath grouper. We are combining electronic tagging data analyses with input regarding current angler actions to develop effective and transparent messaging that may increase survival of these large reef fishes after catch and release.


A Preliminary Assessment of the Effects of Chronic Low-Level Nitrate-Nitrogen on Reproductive Development and Spawning Performance of Captive Adult Red Drum (Sciaenops ocellatus)

Presenter: Shawn Coyle
Institution: Marine Fisheries Enhancement Center
Fish and Wildlife Research Institute
Florida Fish and Wildlife Conservation Commission
Apollo Beach
Florida
Coauthors:
Kerry Mesner | Marine Fisheries Enhancement Center, Fish and Wildlife Research Institute, Florida Fish and Wildlife Conservation Commission, Apollo Beach, Florida
Kaitlyn O’Neil | Marine Fisheries Enhancement Center, Fish and Wildlife Research Institute, Florida Fish and Wildlife Conservation Commission, Apollo Beach, Florida
Casey Murray | Tropical Aquaculture Laboratory, School of Forest, Fisheries, and Genomic Sciences, institute of Food and Agricultural Sciences, University of Florida, Ruskin, Florida
Jason Lemus | Marine Fisheries Enhancement Center, Fish and Wildlife Research Institute, Florida Fish and Wildlife Conservation Commission, Apollo Beach, Florida
Matthew DiMaggio | Tropical Aquaculture Laboratory, School of Forest, Fisheries, and Genomic Sciences, institute of Food and Agricultural Sciences, University of Florida, Ruskin, Florida
Josh Patterson | Tropical Aquaculture Laboratory, School of Forest, Fisheries, and Genomic Sciences, institute of Food and Agricultural Sciences, University of Florida, Ruskin, Florida
Abstract:
Elevated environmental nitrate (NO3-N) is known to be an endocrine disruptor in fish, affecting steroid hormone synthesis. Nitrate is generally considered nontoxic at values found in marine aquaculture systems, yet anecdotal evidence suggests that chronic exposure to nonlethal levels characteristic of recirculating aquaculture systems (RAS) may cause reproductive disruption in red drum (Sciaenops ocellatus). In response, a series of experiments were conducted to assess the effect of nitrate on spawning success. Four 12,000 L independent RAS, each containing three female and two male captive red drum, were used as spawning tanks. For the Nitrate group (n=2 tanks), nitrate was maintained at an average of 46.3 mg/L. Nitrate averaged 6.2 mg/L for the Control group (n=2 tanks). Reproductive development was achieved through photothermal manipulation. Spawning was induced through acute temperature increase. Group fecundity and hatch rate were estimated volumetrically. A subsample of larvae from each planned spawn were raised for 24 days on live foods to determine survival. Blood was drawn monthly from female broodstock to determine steroid, vitellogenin and nitrate levels (n=6 fish per treatment). A Mixed Model ANOVA (P=0.05) was used for comparison of nitrate level on fecundity and broodstock blood chemistry. There was no significant difference (P>0.05) in group fecundity. A Generalized Linear Mixed Model was used to compare hatch and survival of larvae to 24 days for Control and Nitrate groups and no effects of nitrate were found for either parameter. A two-way repeated measures ANOVA indicated a significant effect of time but no effect of nitrate on reproductive indicators in the blood; however, blood nitrate levels were significantly greater in Nitrate than Control groups. Although nitrate accumulates in the blood of red drum, this study indicates that nitrate concentrations of <50 mg/L do not affect commonly monitored spawning performance indicators for red drum.


Filling the Gaps – Monitoring Water Quality and Zooplankton Assemblages in Perdido Bay

Presenter: Amanda Croteau She/Her
Institution: University of West Florida
Coauthors:
Mackenzie Rothfus | University of West Florida
Abstract:
Perdido Bay and its tributary, the Perdido River, serve as the border between Alabama and Florida. As a border system with nearby larger bay systems to the east and west, it suffers from a lack of monitoring from both states. Depending on who you ask, Perdido Bay is either idyllic, protected, and pristine or highly impacted and decimated by industry. During a series of stakeholder engagements, community members and local community science groups expressed concerns about the water quality of Perdido Bay and its associated tributaries, noting a decline in many encrusting organisms that have a larval zooplankton stage. Zooplankton communities are important links in estuarine food webs and are useful bioindicators with shifts in populations, size, and community composition often related to changes in their environment. This project was developed to investigate community concerns and increase spatial and temporal monitoring of the system. Surface and bottom samples were collected monthly for water quality parameters and zooplankton community at 20 fixed locations along the estuarine gradient and tributaries in both states. Vertical profiles for ambient water characteristics were measured. Selected sites include locations where long-term monitoring has occurred as well as new sampling sites to address other areas of concern. This study will also fill data gaps which will aid future restoration efforts. Current datasets are needed to create suitability models for restoration, especially datasets that include benthic and water column data in addition to surface measurements. Understanding various water quality parameter dynamics of a system are critical for assessing the suitability of large-scale habitat restoration such as the oyster restoration efforts currently occurring in the neighboring Pensacola Bay system.


Developing a New Method to Test Relationships Among Habitat Quality Characteristics, Prey Availability, and Sport Fish in an Estuarine Habitat Complex

Presenter: Christopher Crowder he/him *
Institution: University of Central Florida
Coauthors:
Christopher Crowder | University of Central Florida
Linda Walters | University of Central Florida
Melinda Donnelly | University of Central Florida
Geoffrey Cook | University of Central Florida
Abstract:
Sport fish often utilize oyster reef and mangrove shoreline habitats throughout the course of their lives. We must better describe how the quality of these habitats can impact abundance of sport fish by creating different models that categorize habitats in various manners. This study would consider the movement of sport fish between habitats and how the relative proportion and quality of habitat types and abundance of prey within a defined area can influence the presence of sport fish within Mosquito Lagoon and 4 connected estuary state parks. We will start the analysis using established techniques then refine each bayesian model with more information regarding the habitat complex, types of prey available, and information about the sport fish . We hope to use the results from this study to describe the influences of habitat quality and prey availability on sport fish abundance; and create a new method of analyzing mobile fish foraging within a shifting habitat mosaic. This is part of a larger on-going project by corresponding author, Christopher Crowder: ccrowder@knights.ucf.edu


Population trend assessment and population genetics of Saltmarsh Topminnows (Fundulus jenkinsi) in Florida

Presenter: Jonah Cruz
Institution: Florida Fish and Wildlife Conservation Comission
Coauthors:
Chelsea Myles-McBurney | Florida Fish and Wildlife Conservation Commission
Abstract:
The Saltmarsh Topminnow Fundulus jenkinsi are smaller members of the Topminnow family that inhabit brackish tidal marshes along the Gulf of Mexico from Texas to Florida. Within Florida, their known range only includes the Perdido and Pensacola Bay systems. Saltmarsh Topminnows are listed as Threatened in the state of Florida due to their restricted range, severe population fragmentation, and general decline in extent and quality of habitat. Prior to this study, no information on population structure or effective population size for Saltmarsh Topminnows existed within Florida. During this study, a multi-season site-occupancy model was developed to determine population trends of Saltmarsh Topminnows within the Pensacola Bay complex along with establishing a genetic monitoring protocol. Thirty-nine sites were sampled within the Pensacola Bay complex between 2016-2020 using a standardized trapping array. Between 11 February 2016 and 8 July 2020, a total of 1,203 Saltmarsh Topminnows were captured. Trap type was the best predictor of detection probability, and the null model was the best model for colonization and extirpation probability. Results of this study estimated proportion of occupied sites within the study area to be 29% in the summer of 2016 to a maximum of 50% in the spring of 2020. Additionally, 266 Saltmarsh Topminnows were successfully genotyped from seven different locations from the Pensacola Bay complex. Results from this study identified genetically differentiated subpopulations of Saltmarsh Topminnows within the Perdido River, Bayou Grande, Escambia Marsh, Escambia Bay, and the Yellow River Marsh. Future effort should be taken to evaluate the factors that influence Saltmarsh Topminnow dispersal.


Water Quality in Guana Estuary: From Monitoring to Management

Presenter: Nikki Dix she/her
Institution: Guana Tolomato Matanzas National Estuarine Research Reserve
Coauthors:
Jessica Lee | Guana Tolomato Matanzas National Estuarine Research Reserve
Olivia Roorbach | Guana Tolomato Matanzas National Estuarine Research Reserve
Shannon Dunnigan | Guana Tolomato Matanzas National Estuarine Research Reserve
Abstract:
Guana Estuary in Northeast Florida has been valued by humans for centuries. It has also been manipulated by humans for centuries. A portion of the estuary was impounded in the 1950’s to create a lake habitat for waterfowl hunting. In the 1970’s, just prior to many wetland protection regulations, areas north of the lake were developed into what is now a world-famous golf course community. Today, Guana Estuary is protected with an Outstanding Florida Water designation, but threats from urbanization are growing. Since 2017, this highly altered system has been the focus of a publicly and privately funded water quality assessment project. Monthly water samples revealed high levels of nitrogen and algal biomass leading to a state impairment designation for both the river and lake in 2022. Even though most watershed inputs come from a single point at the northern end of the estuary, nitrogen and chlorophyll concentrations peaked 5 km south of that point, suggesting internal processes like sediment recycling and vegetation growth/death are important drivers of water quality. Water management practices in Ponte Vedra (for flood control) and in Guana Lake (for vegetation control) also influence water quality. This baseline information has pointed to a need for water quality restoration in the Guana Estuary. A team from University of Florida and GTMNERR has been working on a grant-funded project to determine nitrogen sources and assess the potential role of shellfish in improving water quality. These data, stakeholder input, and modeling of various restoration strategies will be used to create management recommendations aimed at improving the health of Guana Estuary.


Philometrid Nematodes in the Gonads of Gray Snapper in Offshore Spawning Aggregations off the West Coast of Florida

Presenter: Kaitlyn Doyscher she/her *
Institution: University of Florida
Coauthors:
Debra Murie | University of Florida
Abstract:
Philometrid nematodes parasitize the gonads of various snappers and groupers in tropical and subtropical regions. The larger female philometrids are known to damage the ovaries of fish, and it is therefore speculated that they can affect fish reproduction. The objective of this study was to determine the sex-specific occurrence, frequency, and size of philometrids in Gray Snapper (Lutjanus griseus) during their spawning season off the west coast of Florida. In April to November 2022, Gray Snapper carcasses were collected from recreational fishers onboard headboats fishing offshore at the Middle Grounds off the west coast of Florida. In the lab, fish were measured for length, and the otoliths and gonads were extracted for aging and reproductive processing. Ovaries and testes from a monthly subsample of fish were dissected for philometrid nematodes, with all nematodes counted and measured. Female Gray Snapper had a higher occurrence of philometrid nematodes compared to males (28 versus 12%). Females had nematodes present in every month (April to November) but increased from April (~6%) to a maximum in July (~56%) during the peak of spawning, and then decreased from August to November (<28%). Overall, males had a low occurrence of philometrids (<10%) although it similarly increased during the spawning season (11-22% over July to September). Females that had philometrids present had a maximum of 40 nematodes per pair of ovaries whereas males had a maximum of 12 per testes. In particular, the ovaries of Gray Snapper have larger oocytes and more lipids in the peak months of spawning, which the nematodes utilize for their own sustenance and growth. If the load of parasites impacts the egg production of female Gray Snapper, in particular, then this sex-specific, gonad-parasite may have the ability to impact the reproductive potential of the spawning stock.


Quantifying and Identifying Factors Influencing Length Changes in Popular Freshwater Fishes Preserved in Ice

Presenter: Kirk Dunn
Institution: Florida Fish and Wildlife Conservation Commission
Coauthors:
Jennifer Moran | Florida Fish and Wildlife Conservation Commission
John Saxton | Florida Fish and Wildlife Conservation Commission
Ted Lange | Florida Fish and Wildlife Conservation Commission
Kim Bonvechio | Florida Fish and Wildlife Conservation Commission
Abstract:
Fish length data are important for assessing sportfish populations and establishing and enforcing length-based harvest regulations. Evidence suggests that fish length can change after preservation in ice. These changes can impact comparison of live-caught and post-catch length measurements and therefore angler compliance to regulations, a concern raised by state law enforcement personnel. Similarly, length changes may skew length-based analyses done by fisheries managers. We evaluated TL changes of largemouth bass (Micropterus salmoides), catfishes (Ictaluridae spp.), black crappie (Pomoxis nigromaculatus), and sunfishes (Lepomis spp.) collected in Florida and preserved in coolers of ice for intervals of 3–6 h, 24 h, and 36 h. Our results indicate mean percent shrinkage ranged 0.43%–1.58% among time intervals and fish groups but significantly differed by group and time interval. We found measurement variability and ambient water temperature to be insignificant factors to observed length changes. Where length measurement accuracy is important, fisheries managers should be aware of potential shrinkage of fish post mortality, including during preservation in coolers of ice. As a general recommendation for law enforcement, we suggest absolute shrinkage allowances of 6 mm (0.25 inches) for black crappie and sunfishes and 13 mm (0.5 inches) for largemouth bass and catfishes, when assessing angler compliance to length-based fish regulations after preservation in coolers of ice.


Does mobility matter? Differential survival of two ray species in Tampa Bay during a red tide event

Presenter: Allison Durland Donahou she/her
Institution: Florida Southern College
Coauthors:
Gabriel J. Langford | Florida Southern College
Abstract:
Severe Karenia brevis blooms (red tide) can have extensive impacts on the marine ecosystem, from fish kills to shellfish poisoning. In early July 2021 a severe red tide bloom spread into Hillsborough Bay in northeastern Tampa Bay, causing fish kills on a large scale including Southern Stingrays Dasyatis americana. During this time, no living rays were observed in our sampling areas (eastern Tampa Bay from E.G. Simmons Conservation Park to the Alafia River) and numerous decomposing Southern Rays were observed. Prior to this bloom (June 2021), we caught Southern Stingrays in abundance (n = 15) while we seldom caught Cownose Rays Rhinoptera bonasus (n = 3). During the subsequent 17 months of sampling, zero Southern Stingrays were captured or observed. However, Cownose Rays were captured (n = 70) and many more observed in schools. Based on our observations, the red tide event of July 2021 seems to have decimated the Southern Stingray populations with limited recovery in eastern Tampa Bay. Conversely, the Cownose Ray population seems to be more resilient to the effects of red tide, potentially due to their increased mobility. We hypothesize that Cownose Rays were able to migrate out of the red tide bloom while Southern Stingrays were not, resulting in a decrease in the Southern Stingray population in Hillsborough Bay. Cownose Rays have returned while Southern Stingrays have not, resulting in a shift in community composition in eastern Tampa Bay. The effects of the red tide event in summer 2021 were widespread and are continuing to impact Tampa Bay.


Evaluating stocked, hatchery-reared Rainbow Trout as potential forage for trophy Largemouth Bass in Florida

Presenter: Drew Dutterer
Institution: Florida Fish and Wildlife Conservation Commission
Coauthors:
Shalyn Zappulla | Florida Fish and Wildlife Conservation Commission
Summer Lindelien | Florida Fish and Wildlife Conservation Commission
Allen Martin | Florida Fish and Wildlife Conservation Commission
Abstract:
Stocking catchable-size Rainbow Trout (Oncorhyncus mykiss) in support of put-and-take fisheries is common across North America. In some cases, these fish unintentionally become abundant forage sources for large piscivorous fishes, boosting some individuals to exceptional trophy sizes. This phenomenon was likely responsible for catapulting trophy Largemouth Bass (Micropterus salmoides) fisheries in California into world renown during the 1980s and 1990s. During that time, anglers there caught and documented 19 of the world’s largest known 25 Largemouth Bass from reservoirs regularly stocked with Rainbow Trout. We sought to explore the utility of stocking Rainbow Trout as supplemental forage for Largemouth Bass in Florida, where trophy bass management is a high priority. We monitored the fates of a small number of Rainbow Trout stocked into a 200-acre North Florida lake during winter 2022. Ten trout were implanted with acoustic telemetry tags with depredation sensors; 40 trout were implanted with radio telemetry tags with motion sensors that indicated the binary status of active or inactive; and 41 trout were released into suspended predator exclusion pens to monitor survival in the absence of predation. Our telemetry tags indicated that most trout were rapidly eaten. Predator exclusion pen trials ran from February 1 to May 9, 2022, when the last trout had died from heat stress. Mortality of trout in the holding pens began in mid-March, after several consecutive days of water temperatures exceeding 70°F. No trout remained alive after sustained water temperatures exceeding 75°F. Our results confirmed that there is little threat of long-term survival of the non-native Rainbow Trout in Florida due to warm summertime water temperatures, but our results also suggest that stocking them as supplemental forage for trophy Largemouth Bass is feasible over a 4–5-month period annually during winter and warrants further investigation.


Movement strategy comparison of Common Snook and sub-adult Atlantic Tarpon in two estuaries of varying environmental predictability within Everglades National Park.

Presenter: Cody Eggenberger he/him *
Institution: Florida International University
Coauthors:
Jennifer Rehage | FIU
Rolando Santos | FIU
Ryan James | FIU
Christopher Madden | SFWMD
Abstract:
External factors such as the suite of environmental conditions animals encounter within various habitats influence their movements within a landscape. The spatiotemporal variability of the environmental conditions throughout a landscape, or the environmental predictability, can drive changes in animal movement an elicit the emergence of repeated movement patterns (i.e. movement strategies). These movement strategies, which are a function of an individual’s response to proximate cues within the environment and its cognitive ability, are adaptive traits that therefore often shift spatiotemporally alongside shifts in environmental predictability. Anthropogenic disturbance such as habitat loss and degradation can alter the environmental predictability of a landscape and thus the movement strategies employed by animals. Despite being critical habitat for many recreational fish species, the alteration of freshwater inflow regimes to estuarine environments is of increased concern globally as it’s known to shift environmental conditions spatiotemporally and the environmental predictability of estuaries. Using 7 years of acoustic telemetry tracking data collected from 2016-2022, this research aims to compare and contrast the movement strategy utilization of two estuarine dependent recreational fish species, the Common Snook (Centropomus undecimalis) and sub-adult Atlantic Tarpon (Megalops atlanticus) within two neighboring estuaries of disparate environmental predictability located in Everglades National Park. The goal of this work is to provide an increased understanding of how recreational fish species’ behavior might be influenced by the most common anthropogenic disturbance to estuaries globally- altered hydrology.


Using game cameras to evaluate restoration success and estimate angler effort on Lake Apopka

Presenter: KristieRae Ellis She/Her
Institution: Florida Fish and Wildlife Conservation Commission
Coauthors:
Brandon Thompson | Florida Fish and Wildlife Conservation Commission
Andrew Marbury | Florida Fish and Wildlife Conservation Commission
Abstract:
Historically, Lake Apopka was a high-quality Florida Bass Micropterus floridanus fishery and considered one of Florida’s most important recreational fishing lakes. By the 1960s, degradation of adjacent marsh habitat and construction of water control structures led to poor water quality, vegetation loss, and collapse of the fishery. In 1977, less than 1% of Lake Apopka contained aquatic vegetation and by 1982, total fishing effort was estimated at 2,104 hours. In response, several large-scale restoration and stocking projects took place, with the goal of improving water quality and increasing lake use by recreational anglers. Game cameras provided an efficient and low-cost option to evaluate angler effort. From 2012 to 2022, game cameras placed at key access points around Lake Apopka were used during peak season (November to May) to determine number of fishing trips, trip duration, and number of anglers. Initially, total angler effort was low, averaging 4,961 hours. However, the rapid expansion of submersed aquatic vegetation in Lake Apopka from 2020 to 2022 improved water quality and substantially increased rearing habitat and cover for young-of-year and juvenile bass. Increased fish habitat, combined with stocking and promotional efforts, generated a renewed interest in Lake Apopka. During the 2021-2022 game camera creel, total angler effort was estimated at 25,526 hours, over five times the average effort of previous years. However, as angler effort on Lake Apopka has increased, the use of game cameras has become more challenging, requiring more time to interpret images. As a result, temporal subsampling of camera data has been proposed as an alternative to analyzing every captured image.


Evaluation of The Eastern Mosquitofish (Gambusia holbrooki) As a Biocontrol of the Tropical Clawed Frog (Xenopus tropicalis)

Presenter: Katie Everett she/her *
Institution: UF/IFAS Tropical Aquaculture Laboratory
Coauthors:
Quenton Tuckett | UF/IFAS Tropical Aquaculture Laboratory
Jeffrey Hill | UF/IFAS Tropical Aquaculture Laboratory
Abstract:
In 2013, a homeowner collected two non-native tropical clawed frogs (Xenopus tropicalis) in Riverview, FL. In 2016, a breeding site was identified several miles away. Since these initial discoveries, clawed frogs have been found in more than 20 additional water bodies within a roughly 1600 ha area, many of which are breeding sites. Eradication of established species is rare but can be achieved when their populations are still small and geographically restricted. Much of peninsular Florida is likely to be suitable for the spread of the clawed frog; therefore, immediate action must be taken if the species is to be eradicated and additional spread prevented. Preliminary experimentation indicated that the native eastern mosquitofish (Gambusia holbrooki) will kill clawed frog tadpoles by attacking their tails and other soft tissues. To test the efficacy of the mosquitofish as a potential biocontrol agent, mosquitofish were stocked into each of the known clawed frog ponds, beginning in 2021. The ponds were then sampled regularly for clawed frog adults, tadpoles, fish, and any other species. At the same time, we tested the survival of adult clawed frogs, froglets, and two size classes of tadpoles when exposed to mosquitofish. During these predation trials, we observed rapid high mortality in tadpoles kept with mosquitofish, but minimal interactions between the fish and adult frogs. In the ponds, tadpole detections declined significantly after the introduction of mosquitofish. Overall adult frog captures declined by 39.6% from 2021 to 2022. However, more time and experimentation is needed to determine whether this will be a viable long-term solution.


Environmental DNA Analysis of Forage Fish Diversity and Distribution in the Indian River Lagoon

Presenter: Emily Farrell She/Her *
Institution: University of Central Florida
Coauthors:
Richard Paperno | Florida Fish and Wildlife Conservation Commission
Michelle Gaither | University of Central Florida
Abstract:
The Indian River Lagoon is one of the most species rich estuaries in the U.S., providing habitat to over 400 species of fish including critical forage fishes, such as menhaden, anchovy, and sardines, and their predators. The Florida Fish and Wildlife Conservation Commission (FWC) conducts monthly seine surveys in the IRL (Indian River Lagoon), which provide the basis for most fisheries resource management and conservation decisions in the region. However, key forage fish species may be systematically overlooked by these surveys due to gear bias. Community surveys using environmental DNA (eDNA) – DNA passively shed by aquatic organisms into the water column – is a new approach that shows great promise for fisheries monitoring that avoids many of the biases and challenges of traditional methods. This study aims to fill the forage fish data gap by utilizing eDNA metabarcoding to conduct a survey in the IRL and to create a rapid and cost-effective toolkit that will complement existing survey efforts. As part of this effort, we have collected water samples alongside FWC’s monthly surveys at two time periods (fall and spring) from sites across the northern IRL. Using protocols optimized in our lab at the University of Central Florida, we have extracted DNA from these samples and prepared Illumina libraries using 16S primers designed for fishes. Here we present species composition and individual occurrence records at each sample site and compare these with data obtained from the FWC survey to evaluate the relative strengths and weaknesses of each method.


Emerging signs of ecological stress in Tampa Bay reinvigorates partnerships to preserve and restore seagrass habitats in support of healthy nekton communities

Presenter: Kerry Flaherty-Walia she/her
Institution: Tampa Bay Estuary Program
Coauthors:
Marcus Beck | Tampa Bay Estuary Program
Meagan Schrandt | Florida Fish and Wildlife Conservation Commission
Edward Sherwood | Tampa Bay Estuary Program
Abstract:
The growth and distribution of seagrasses are influenced by many interrelated factors, including light penetration, nutrient levels, freshwater inflow, and turbidity. Seagrass-bed architecture, seagrass species composition, and water conditions can also affect how fish and macroinvertebrates (nekton) use seagrass habitats for refuge and foraging. After decades of declining seagrass coverage in Tampa Bay, the Tampa Bay Estuary Program set a goal of restoring seagrass coverage to levels found in the estuary in the 1950s. In part through collaboration among regional partners to reduce nitrogen loads, this restoration goal was surpassed with seagrass coverage reaching a record 41,655 acres in 2016. Since then, however, compounding stressors, such as changing rainfall patterns, warmer water temperatures, and obstructions to tidal circulation are likely affecting the persistence of seagrass meadows with 11,518 acres lost between 2016 and 2022. An index developed to communicate overall nekton health to stakeholders also reflected stress on nekton communities during this period in the upper bay where most seagrass loss occurred. To determine the environmental drivers and species associated with nekton community changes in varying seagrass conditions, we analyzed fisheries-independent monitoring data collected using 21.3-m seines in Tampa Bay from 1998–2021. The effects of spatial variation in seagrass loss on nekton diversity and community structure were evaluated in the major bay regions (Old Tampa Bay, Hillsborough Bay, Middle Tampa Bay, Lower Tampa Bay) that are used to measure other indicators of bay health (i.e., water quality, seagrass, benthic invertebrates). By synthesizing and communicating Tampa Bay’s ecology in an accessible and timely manner, regional scientists, community members, industry, and policy makers have learned of the broader impacts of recent seagrass habitat losses in the estuary. These stakeholders are being asked to renew collaborative efforts to preserve and restore seagrass habitats that support healthy nekton communities.


Introductions, spread, reproduction, and impacts of tilapia (Oreochromis spp.) in Florida

Presenter: Jonathan Freedman he/him/his
Institution: CNSS / USGS
Coauthors:
Wesley Daniel | USGS
Abstract:
Although many fish species have been introduced to the United States, only a fraction of those are considered invasive, defined as having negative ecological or economic impacts. Several species of tilapia have been intentionally introduced, often to provide food resources for humans or predatory fishes, or to control algae and other vegetation. Incidental or accidental relocation may also occur. The USGS Nonindigenous Aquatic Species (NAS) Database tracks occurrences of >1,390 aquatic species throughout the United States and her territories. In addition to observation and capture data, the NAS Database compiles literature on ecological, economic, and human health impacts of nonindigenous species. I will review the pathways and vectors of introduction and spread of three common and abundant tilapia species – Oreochromis aureus (Blue Tilapia), O. mossabicus (Mozambique Tilapia), and O. niloticus (Nile Tilapia) – and their cumulative and relative impacts with focus on Florida. I will also present on the use of satellite imagery to estimate and compare relative reproduction over time using nest density in Florida’s freshwater springs.


Measuring fish movement in Everglades National Park using Floy Tags

Presenter: Bridgette Froeschke
Institution: The University of Tampa
Abstract:
Examining fish movement is essential for conservation efforts, fisheries management, ecological understanding, and tracking the impacts of invasive species on ecosystems. Furthermore, understanding how fish move and behave can help fisheries managers make informed decisions to help regulate and/or eradicate invasive species. Movement patterns of both native and invasive fish species were examined at multiple locations within Everglades National Park. Five-hundred fish including Spotted Sunfish, Bluegill, Warmouth, Mayan Cichlid, Oscar, Blue Tilapia, and Green Spotted Tilapia were collected using rod and reel and minnow and pinfish traps. All fish were measured and weighed prior to tagging using Floy Tags and released at the same spot of collection. All fish were tagged within a 3-day period. Each location was resampled monthly to determine any movement among the sites and potential home ranges. Results were examined between native and invasive species and compared among all sites. This is an on-going study and fish will continue to be tagged and sampled for recapture. This study will aid in conservation of Everglades National Park by identifying important habitats, migration patterns, and to develop effective conservation plans and management strategies.


Economic feasibility of on-growing lobsters in Florida

Presenter: Taryn Garlock
Institution: University of Florida
Coauthors:
Taryn Garlock | School of Forest, Fisheries, and Geomatic Sciences, University of Florida
Frank Asche | University of Florida
Abstract:
Landings of Florida spiny lobster are misaligned with demand in the Chinese live market, the most valuable outlet for Florida spiny lobster. The current management regime has resulted in the majority of spiny lobsters being harvested in the first few months of the season (i.e., August through October) when price and demand in the live market are at its lowest. Harvested lobsters are also susceptible to higher mortality rates during this time due to high water temperatures. On-growing of wild legal-sized lobsters in tanks prior to export is being explored as a means to grow lobsters to a more profitable size and align supply with peak demand associated with Chinese holidays such as the Lunar New Year in January. We develop a bioeconomic model that combines production and economic data collected from on-growing experiments to explore the economic feasibility of on-growing lobsters for the live export market.


Ecological Modeling to Support Management of Shifting Black Seabass Stocks

Presenter: Lauren Gentry She/her
Institution: Fish and Wildlife Research Institute
Coauthors:
David Chagaris | University of Florida
Lucas McEachron | Florida Fish and Wildlife Research Institute
Shanae Allen | Florida Fish and Wildlife Research Institute
Abstract:
The South Atlantic Fisheries Management Council has observed a consistent decrease in the availability of black seabass (Centropristis striata) in federal waters of North Carolina, South Carolina, Georgia, and the east coast of Florida. Likely hypotheses for shifting stocks include increasing water temperatures pushing populations north or into deeper water, changes to productivity affecting prey availability, local stock depletion, and aggression by red snapper (Lutjanus campechanus). This ongoing study is attempting to use ecological modeling to determine the likely causes of these stock shifts and inform future black seabass management. The existing South Atlantic Reef Fish (SARF) model is an Ecopath with Ecosim (EwE) model developed to explore the ecological dynamics of snappers, groupers, and other managed reef fish on the U.S. southeast Atlantic coast. We are developing an additional Ecospace module to include habitat and environmental driver maps, dispersal rates, species-habitat preference functions, fishing effort maps, and spatial abundance data from fishery surveys. Scenarios will be designed to test the potential impact of each hypothesis on black seabass stock shifts. We expect the results will be used to inform ecologically robust management decisions that are sensitive to the changing ocean climate and shifting habitats.


Mercury Accumulation and Trophic Position of a Dominant Mesopredatory Fish Family (Alepisauridae) and Prey in the Pelagic U.S. South Atlantic Bight

Presenter: Daria Ghegan She/Her
Institution: Nova Southeastern University
Coauthors:
Ellyn Willse | Nova Southeastern University
James Gelsleichter | University of North Florida
Amy Hirons | Nova Southeastern University
David Kerstetter | Nova Southeastern University
Abstract:
Numerous studies of smaller neuston and upper-level predatory vertebrates feeding in the mesopelagic zone (200-1000 m depths) have suggested a reservoir of mercury that can transfer into apex predators at higher trophic levels. However, little is known regarding mercury transfer in mesopredators. We present novel trophic position and (total) mercury level data on two mesopredatory alepisaurid lancetfishes and 13 of their main prey items, including invertebrates, cephalopods, and mesopelagic fishes. Mean mercury levels in the alepisaurids were 23.67 μg/kg (wet wt), with individuals in larger size classes (101-130cm, >130cm) having higher levels than smaller size classes (<50cm, 50-100cm). In the prey items, mean mercury levels were 13.80 μg/kg (wet wt), with argonauts (36.70 μg/kg) and combined teleost fishes (21.91 μg/kg) having higher levels than all other invertebrates combined (5.86 μg/kg), and the differences in mean mercury levels between predators and prey were highly significant. Lancetfishes are nonselective predators and often engage in cannibalistic feeding behavior. Dietary information in combination with mean trophic positions of combined lancetfish and prey (3.82, 3.05 respectively) suggests bioaccumulation of mercury throughout the food web. Combined, lancetfish also showed a strong correlation of mercury and length, providing further evidence of bioaccumulation. This study provides the first mercury content analysis for a mesopelagic mesopredator with an opportunistic diet.


Estimating gag (Mycteroperca microlepis) nursery origin with otolith stable isotope signatures

Presenter: Hannah Gottesman she/her *
Institution: Interdisciplinary Ecology
School of Natural Resources and Environment
Institute of Food and Agriculture Science
University of Florida
Coauthors:
William Patterson III | Fisheries and Aquatic Sciences, School of Forest, Fisheries, and Geomatics Sciences, Institute of Food and Agriculture Science, University of Florida
Ernst Peebles | College of Marine Science, University of South Florida
Theodore Switzer | Fish and Wildlife Research Institute, Florida Fish and Wildlife Conservation Commission
Susan Lowerre-Barbieri | Fisheries and Aquatic Sciences, School of Forest, Fisheries, and Geomatics Sciences, Institute of Food and Agriculture Science, University of Florida; Movement Ecology and Reproductive Resilience (MERR), Fish and Wildlife Research Institute, Florida Fish and Wildlife Conservation Commission
Abstract:
The extent of dispersal following nursery egress affects population connectivity and structure for reef fishes with an inshore juvenile stage, including gag (Mycteroperca microlepis), but it is unknown whether the nearest West Florida Shelf (WFS) estuarine nurseries sustain Florida’s nearshore gag fishery in heavily fished Panhandle and Big Bend regions. We used an archived dataset of age-0 gag from the 2009 (n=80), 2010 (n=39), and 2012 (n=78) year classes to test the ability of otolith chemistry to distinguish WFS nursery regions then used those chemical signatures to estimate the source(s) of nearshore gag in the 2009 (age-2 n=3, age-3 n=15) and 2010 (age-1 n=6, age-2 n=34) year classes. Age-0 gag otolith chemistry differed between nurseries and year classes, and the otolith constituents which differed varied year-to-year. Otolith trace elements lacked consistent spatial patterns, but otolith oxygen (d18O) and, to a lesser extent, carbon (d13C) stable isotopes exhibited persistent differences between northern and southern nursery regions. This latitudinal pattern produced a reliable chemical tag, so we fit a logistic generalized additive model with age-0 gag d13C and d18O and applied it to the nearshore gag. We found most of the nearshore gag across the WFS were estimated to originate in southern nurseries, while those estimated to originate in northern nurseries were only observed in the north. Our preliminary findings suggest both local and remote sources support nearshore fishery abundance, providing timely insight about appropriate management scales for the Gulf of Mexico gag stock, which is estimated to be overfished and undergoing overfishing (SEDAR 2021). In addition to investigating year-to-year variation in regional chemical signatures to account for error in our model estimates, we investigated decadal shifts in these signatures using age-0 gag captured in 2020 (n=71) and 2021 (n=22) to understand the effects of changing environmental conditions, such as climate and hydrology, on otolith chemistry.


Using Annuli Deposition to Evaluate Effects of Hatchery Induced Spawning of Red Drum Sciaenops ocellatus

Presenter: Kiley Gray She/her
Institution: Florida Fish and Wildlife Conservation Commission
Coauthors:
Jessica Carroll | Florida Fish and Wildlife Conservation Commission
Kerry Mesner | Florida Fish and Wildlife Conservation Commission
Abstract:
Otoliths are calcium carbonate structures found behind the brain of bony fish and are used by the fish for equilibrium and sound detection. Scientists most commonly use otoliths for age determination. Environmental variables and life events such as temperature fluctuation and spawning can lead to changes in annulus deposition. Our goal in this study was to use variations in annulus deposition as an indicator for stress in a sample of Red Drum Sciaenops ocellatus from an aquaculture facility. Red Drum annulus deposition typically occurs between the late winter and early spring, which creates easily discernable growth intervals on otolith sections. Florida Fish and Wildlife Conservation Commission’s Stock Enhancement Research Facility conducted an experiment to assess the spawning contribution and operational cost benefits of having one large brood stock population in a large tank compared to smaller populations housed in several tanks. As part of this experiment, detailed records were kept of potential stressful events for 26 fish, including initial catch date, movement into experimental tanks, induced spawning, etc. These known events were correlated to disruptions in annulus deposition visible on otolith sections in order to identify any impacts on the growth rates of these fish. Preliminary results of the analysis are that while Red Drum growth was clearly disrupted by movement to, and within, the aquaculture facility, overall growth patterns demonstrated resiliency and resumed regularity after disruptions.


Assessing anthropogenic impacts on submerged aquatic vegetation (SAV) in central Florida springs

Presenter: Susanna Harrison she/her
Institution: FWRI
Coauthors:
Jay Holder | FWRI
Kimberly Bonvechio | FWRI
Earl Lundy | FWRI
Abstract:
In recent years, submerged aquatic vegetation (SAV) has substantially declined in many of the spring headwaters and runs of the middle St. Johns River (SJR) Basin. SAV is a critical component in the SJR basin ecosystem, functioning as habitat, nursery grounds, and cover for sportfish and other aquatic taxa. Many of these springs experience heavy recreational use, particularly in designated swimming areas around the spring vents. The purpose of this study is to quantitatively assess the extent to which human activities impact SAV health and abundance in the spring vent areas at Alexander Springs and Juniper Springs, two high-use springs in Ocala National Forest. We used trail cameras to record human activity in these swimming areas throughout the calendar year and conducted monthly photographic surveys to document changes in SAV coverage and condition over time. We are currently using the data collected from the trail camera photos and SAV surveys to evaluate correlations between recreational use and SAV degradation. These data can help to inform and support future recreational management decisions to prevent further SAV loss in SJR headwater springs, such as protective zones, temporary closures, and gear restrictions.


Impacts of Hurricane Michael on Shoal Bass within the Chipola River

Presenter: Ryan Henry
Institution: Florida Fish and Wildlife Conservation Commission
Coauthors:
Brandon Barthel | Florida Fish and Wildlife Conservation Commission
Andy Strickland | Florida Fish and Wildlife Conservation Commission
Stephen Stang | Florida Fish and Wildlife Conservation Commission
Bryan Winston | Florida Fish and Wildlife Conservation Commission
Abstract:
Shoal Bass Micropterus cataractae are listed as a species of greatest conservation need by the
Florida Fish and Wildlife Conservation Commission. The only known naturally reproducing
population in Florida is found in the Chipola River. Hurricane Michael devastated the Chipola
River in 2018, and several fish kills were documented in the immediate aftermath of the storm.
Major declines in Shoal Bass relative abundance were observed in 2019. The objectives of our
study were 1) to conduct a mark-recapture population estimate to compare the abundance of
the Shoal Bass population to earlier estimates produced from sampling in 2009-2011, 2) to
estimate the effective population size of the Shoal Bass population and 3) to assess the current
state of hybridization between Shoal bass and non-native black bass species within the Chipola
River. A mark recapture population estimate took place over 9 days in October and November
2021. The Schnabel population estimate suggested that there were 1,039 Shoal Bass) from Spring
Creek to Johnny Boy Landing in fall 2021. This is 52% lower than the estimate produced when the
same stretch was sampled in 2009. Genetic results indicate that the Chipola River Shoal Bass
population currently has very low levels of hybridization with non-native black bass. The effective
population size of the Shoal Bass population was estimated to be less than 50. This suggests the
population would be vulnerable to introgressive hybridization, genetic diversity loss, and
inbreeding depression if the population remains at this level.


Trophic interactions of important recreational fisheries in Tampa Bay, Florida

Presenter: Megan Hessel *
Institution: The University of Tampa
Coauthors:
Alyee Hodges | The University of Tampa
Sterling Stewart | The University of Tampa
Bridgette Froeschke | The University of Tampa
Abstract:
Understanding trophic interactions provides a comprehensive framework for the variable ecological patterns exemplified by recreational fisheries. This study focuses on determining trophic interactions among fisheries in both Tampa Bay and the Gulf of Mexico. More specifically, we examined the food web interactions among snapper species (Gray Snapper and Lane Snapper), White Grunt, pinfish species, and Sheepshead collected both in Tampa Bay and the Gulf of Mexico. There is little information known about the individual diets or a comprehensive comparison among the species. All fish were dissected and stomachs were initially put into 10% neutral buffered formalin, then transferred to water for 24 hours, and then finally transferred to 70% denatured ethanol. The stomachs were sorted through using a dissecting microscope and stomach content was categorized. Using the weight of each prey item, the percent stomach content was determined for each category. Diet composition was similar among locations and habitats. The overall diet composition consisted of 55% crab, 19% shrimp, 18% sediment, 6% fish, and 1% shell. Most fish collected along seawalls and oyster beds had diets composed primarily of crabs and those collected in artificial reefs/bridges had diets composed mostly of fish. This project provides important information in understanding the ecological role that fish play in Tampa Bay and the Gulf of Mexico and aids in crucial information needed for management.


Estimating Tournament Release Mortality for Largemouth Bass

Presenter: Ryan Howard he/him
Institution: Florida Fish and Wildlife Conservation Commission
Coauthors:
Ted Lange | Florida Fish and Wildlife Conservation Commission
Brandon Thompson | Florida Fish and Wildlife Conservation Commission
Scott Bisping | Florida Fish and Wildlife Conservation Commission
Abstract:
Mortality of Largemouth Bass Micropterus salmoides floridanus caught during weigh-in style tournaments was estimated using custom designed holding pens. Bass caught during eleven summer and two winter FWC permitted bass fishing tournaments were placed in the holding pens alongside reference fish collected via boat electrofishing. Reference fish were used to identify possible non-tournament related effects on mortality. Estimates and timing of delayed mortality were calculated for tournament-caught bass by checking the holding pens daily for nine days post-tournament. Delayed mortality was added to the initial mortality (percentage of expired fish at the tournament weigh-in) in order to estimate total release mortality. The average total release mortality of tournament-caught bass was 41% (N=11) in summer, and 7% (N=2) in winter. Reference fish during the summer tournaments experienced a total release mortality of 9%, while the winter reference fish suffered zero mortalities. Larger bass (>20’’) (low sample size) have not demonstrated any higher mortality than smaller bass (<, =20’’). More data will be collected across a wider variety of systems and tournament clubs to better estimate the mortality of tournament-caught bass in Florida.


Oh, the places they’ll go! Seasonal movements of juvenile Gulf Sturgeon in Pensacola Bay watershed

Presenter: Kirsten Humphries
Institution: Florida Fish and Wildlife Conservation Commission – Fish and Wildlife Research Institute
Coauthors:
Bradford Warland | Florida Fish and Wildlife Conservation Commission
John Knight | Florida Fish and Wildlife Conservation Commission
Abstract:
Juvenile Gulf Sturgeon (Acipenser oxyrinchus desotoi) movements and estuarine habitat use in the Pensacola Bay watershed are currently being monitored in an ongoing 4-year project that commenced in 2020. For the first three years of this study, age-1 to age-5 juvenile Gulf Sturgeon were tagged with Vemco V7 or V9 acoustic transmitters during the spring, summer, and fall. Tagged individuals were then monitored by acoustic receivers (n=~70) in the Pensacola Bay watershed. Coordinated seasonal movements were observed in the Yellow River. An apparent relationship between age or size, and habitat range during the winter period was observed by all tagged individuals. Individuals age-1 to age-3 demonstrated high fidelity to the river mouths during winter estuarine movements, with age- 1’s having the highest usage of the river mouth. Age 4+ demonstrated the furthest range in estuarine movements. Individuals were observed inhabiting shallow water areas (<2 meters) for significant periods of the winter. The vulnerability of these individuals while in shallow water habitat needs to be further studied. Understanding habitat use of juvenile Gulf Sturgeon is crucial in aiding future conservation efforts for the recovery of the species.


Examining residency in cobia (Rachycentron canadum) on the east coast of Florida using passive acoustic telemetry

Presenter: Dayna Hunn
Institution: Florida Fish and Wildlife Research Institute
Coauthors:
Joy Young | Florida Fish and Wildlife Research Institute
Jim Whittington | Florida Fish and Wildlife Research Institute
Abstract:
Understanding the migratory patterns of fish stocks is essential for effective management strategies, including protection of spawning areas and migratory corridors and allocating harvest quantities. Cobia (Rachycentron canadum) is a species of coastal pelagic fish that inhabits a wide area in tropical and subtropical seas. In the southeastern United States, cobia inhabit offshore, nearshore, and inshore waters from Texas through Massachusetts. They undertake seasonal migrations from overwintering grounds in Florida to spawning grounds in the Gulf of Mexico (GOM) and Atlantic (SA) coasts during spring and summer. Historically, cobia were managed as a single stock but are now managed as two stocks with the dividing line at the Florida/Georgia border. Previous movement studies aimed at examining movement around the stock line revealed a portion of cobia tagged on the east coast of Florida may not undergo spawning migrations into the GOM. To investigate a possible resident population of cobia, residency indexes were created for 26 cobia tagged with acoustic transmitters on the east coast of Florida from 2018 to 2022. Detection data were collected from arrays in the FACT and iTAG networks. Per year-season, cobia were detected on average from 8 – 12 days, with a maximum of 26 days. Cobia showed a variety of movement patterns and residency. Five fish were only detected in a single geographic region, while five fish were observed in four or more. Residency was highest in the summer (0.84 ± 0.12) and lowest in the spring (0.54 ± 0.18). Six fish were detected in the keys or west coast of Florida, suggesting a Florida resident population. Future analysis will include examination of factors influencing residents versus migrants.


Stomach Content Comparison Between the Recently Discovered Bullseye Snakehead (Channa marulius), and Two Top-level Predators, Butterfly Peacock Bass (Cichla ocellaris), and Largemouth Bass (Micropterus salmoides), in a Natural Lake System in Southeast Florida

Presenter: Brian Hutchinson
Institution: Florida Fish and Wildlife Conservation
Coauthors:
Kelly Gestring | Florida Fish and Wildlife Conservation Commission
Shelby Stanley | Florida Fish and Wildlife Conservation Commission
Abstract:
Abstract—The bullseye snakehead (Channa marulius) is an established, invasive freshwater fish that was first documented in Florida canal systems in 2000. Bullseye snakehead have expanded their range into urban canals in south central Palm Beach County. Lake Ida, in southeast Palm Beach County, is one of the most natural lakes in the known range of bullseye snakehead. Despite the long-term presence of bullseye snakeheads in canals associated with Lake Ida, they were first documented in the lake on December 12th, 2018. Lake Ida is a popular fishery for largemouth bass (Micropterus salmoides) and butterfly peacock bass (Cichla ocellaris), two of south Florida’s most socioeconomically important sportfish species. To determine potential impacts of the bullseye snakehead, stomach contents were examined for each of these co-occurring top-level predators. A two-year study was conducted to collect and compare the stomach contents of these species. The highest Index of Relative Importance (IRI) values were for fish in the three species, particularly in butterfly peacock. Largemouth bass and bullseye snakehead had higher IRI values for crustaceans and insects, indicative of diet generalists and opportunistic predators. Additionally, bullseye snakehead had a more diverse diet consisting of higher IRI values of amphibians and reptiles compared to the other species. The data suggests a high degree of overlap in diet between the three species, but the highly generalist feeding strategy of bullseye snakehead may lessen the effects on shared prey resources within Lake Ida.


Movement and Survival of Largemouth Bass in the Restored Kissimmee River

Presenter: Reid Hyle he him
Institution: FWRI Freshwater Fisheries Research
Coauthors:
Rachel Grey | USFWS
Jason O’Connor | FWRI FFR
Brittany Bankovich | FWRI GIS
Charles Hanlon | SFWMD
Steven Bousquin | SFWMD
Tanner Beagell | FWRI FFR
Brad Fontaine | FWRI FFR
Arthur Bernhardt | FWRI FFR
Abstract:
The Kissimmee River Restoration Project is one of the largest river restoration projects in the world. The 166 km meandering Kissimmee River was transformed into the 90 km long, 100 m wide, 9 m deep C-38 canal during aggressive flood control and land “reclamation” projects in the 1960s. The immediate negative impacts on fish and wildlife demanded restoration. By 2009, 64 km of river channel had been reflooded and 5,000 ha of floodplain reconnected by infilling pools B and C of the canal. Though partially restored, the river was still subject to flood-control hydrology. Water quality improved in the restored reaches but frequent fish kills were still observed and the fish community reflected dissolved oxygen impairment going into 2019. We used radio telemetry of Largemouth Bass (Micropterus salmoides) to track movement, habitat use, and survival within the restored river and to test for emigration from upstream during 2020 and 2021. We implanted radio transmitters in 50 adult ( 980 g TW) Largemouth Bass in each of January 2020 and 2021 with 30 distributed in the restored river and 10 each in Lake Kissimmee and Pool A C-38 canal. These were monitored by passive stations and active tracking. The two water years differed in the magnitude and timing of flows and subsequent water quality. The result was total annual mortality of fish in the river of 89% in 2020 and 32% in 2021. The few fish that survived in 2020 were fish that vacated the restoration area. Bass readily used off-channel areas during the spawning season when stages provided access. However, floodplain use was limited to near-channel sites and appeared to be restricted by dense invasive plant growth. Stage duration appears to have a significant impact on the quality of water and habitat for fish in the restoration area.


Bycatch analysis in a 20+ year study on American eel (Anguilla rostrata) recruitment into the Guana River system and its implications for a commercially valuable fishery

Presenter: Corey Hymel *
Institution: University of North Florida
Coauthors:
Emily Sapp | University of North Florida
Eric Johnson | University of North Florida
Kelly Smith | University of North Florida
Abstract:
The American Eel (Anguilla rostrata) is a catadromous species of ecological and economic importance that is at near historically low population levels. Since 2001, the University of North Florida and the Florida Fish and Wildlife Conservation Commission have been monitoring the annual recruitment of young-of-year American eels into the Guana River system. A standardized dip-netting technique is performed in a water control structure (Guana Dam) as glass eels migrate upstream into freshwater. We have noticed a decline in annual catch per unit effort (CPUE) over the past 23 years with a consistent downward trend since 2010. In recent years, CPUE has declined from the long-term average (0.59 eels dip-1), with an all-time low during the 2023 recruitment season (2020: 0.22, 2021: 0.09, 2022: 0.02, 2023: 0.02). Because eel recruitment is low, bycatch has recently become a large focus of these seasonal collections. Previous years have reported relatively large numbers of ctenophores (around 0.5 dip-1) while the 2023 season’s bycatch is relatively lower. The absence of ctenophores in this year’s collections may explain an increased abundance of Scianidae bycatch, especially in large recruitment events of spot (Leiostomus xanthurus). Fishes of the family Sciaenidae include the recreationally and commercially valuable Atlantic croaker, weakfish, and red drum. We believe that recent changes in water management strategies at the dam may be a factor in decreased eel recruitment and changes in bycatch composition.


Recruitment of American eels (Anguilla rostrata) to a northeast Florida estuary: Effects of a changing climate on early life history

Presenter: Eric Johnson
Institution: University of North Florida
Coauthors:
Kelly Smith | University of North Florida
Corey Hymel | University of North Florida
Emily Sapp | University of North Florida
Kimberly Bonvechio | Florida Fish & Wildlife Conservation Commission
Abstract:
Changes in global climate are predicted to have numerous effects on fish and fisheries including changes in growth rates, latitudinal range shifts, and alteration of the timing of key life history events such as spawning and recruitment. Climate effects may be particularly pronounced for species like the American Eel (Anguilla rostrata), whose complex life history includes marine, estuarine and freshwater stages. The American Eel is a species of ecological and economic importance to the western north Atlantic and Gulf of Mexico; however, eel populations have been declining across the Atlantic coast prompting concerns over population and conservation status. To assess historic trends in abundance and to examine the phenology of eel recruitment to northeast Florida, we estimated annual glass eel recruitment (catch-per-unit-effort; CPUE) from 2001-2021. Glass eels were collected in northeast Florida at a single fixed station in the Guana-Tolomato-Matanzas (GTM) National Estuarine Research Reserve on dark flood tides during winter. Overall, we observed (1) a significant decline in eel CPUE from a period of high, but variable, abundance in early years (2001 to 2004) to a sustained period of low abundance from 2005 to present, and (2) a variable but significant trend of earlier recruitment of glass eels over the 21-year period of the survey and estimate an approximately 18-day shift in mean recruitment date (-0.87 days year-1). Our results contribute to growing evidence of changes to American eel recruitment dynamics over a period of rapidly changing climatic conditions. Understanding the effects of a changing climate on fish life history is useful for agencies seeking to more effectively manage this important resource. Moreover, this collaborative partnership (FWC, UNF, GTM NERR) allows for the cost-effective collection of valuable long-term data while also providing meaningful research opportunities for undergraduates and training of the next generation of fisheries scientists.


Hydrodynamic form and function of hammerhead sharks: ontogenetic and ecological considerations

Presenter: Sam Johnson He/His/Him *
Institution: The University of Tampa
Coauthors:
Alexandra Butler | The University of Tampa
Dr. Daniel Huber | The University of Tampa
Dr. Michael Slattery | The University of Tampa
Abstract:
Hammerhead sharks are well known for their unique head morphology known as the cephalofoil, which has been studied for both its sensory advantages and its possible enhancement of hydrodynamic efficiency, specifically as a lift-generating structure. This project analyzed the cephalofoils and fins of S. lewini, S. mokarran, and S. tiburo (the scalloped hammerhead, great hammerhead, and bonnethead sharks) using morphometric analysis to determine changes in the size and shape of these structures with respect to the habitats used by these species. It was predicted that these structures would be smallest relative to body size in the coastal dwelling S. tiburo to facilitate maneuverability and largest relative to body size in the pelagic S. mokarran to facilitate cruising. Furthermore, it was hypothesized that these structures would grow isometrically in both species given that they spend their entire lives in a single habitat type (coastal and pelagic, respectively). In contrast, it was hypothesized that S. lewini would have intermediate-sized cephalofoil and fins relative to body size and that these structures would grow with positive allometry in association with the transition from coastal habitats (juvenile stage) to pelagic habitats (adult stage). Specimens were chosen for analysis to represent the size range of each species. Photographs of the cephalofoil and fins from each specimen were first post-processed with tpsDig2 and then analyzed with MorphoJ to determine sizes and shapes, and scaling patterns were analyzed using linear regressions in JMP Pro 11.


Assessing Fall Spawning Dynamics of Fishes on the West Florida Shelf Using DNA Barcoding

Presenter: Keith Keel He/him *
Institution: University of South Florida College of Marine Science
Coauthors:
Makenzie Kerr | USF College of Marine Science
Glenn Zapfe | NOAA Fisheries
Chris Stallings | USF College of Marine Science
Ernst Peebles | USF College of Marine Science
Mya Breitbart | USF College of Marine Science
Abstract:
Identifying spawning areas for commercially and ecologically important species is of great
importance for fisheries conservation and ecosystem-based management. Additionally, further
understanding how environmental and geographical parameters affect the spawning dynamics of
fishes is increasingly more relevant as temperatures and oceanic conditions continue to change
due to climate change. This study used genetic barcoding to identify thousands of fish
eggs collected from the West Florida Shelf during September 2013, 2014, and 2019. Fish eggs
were collected on National Oceanic and Atmospheric Administration (NOAA) Southeast Area
Monitoring and Assessment Program (SEAMAP) cruises using a continuous underway fish egg
sampler (CUFES) attached to the ship’s hull that collects fish eggs at a 3m depth. So far, 2013,
2014, and 2019 fish eggs have all been processed and identified, and when combining all three
years, a total of 84 unique species and 94 unique taxa were identified from 4,464 fish eggs.
Species of interest that were collected and identified with relatively high frequency included:
Lutjanus campechanus (northern red snapper), Rhomboplites aurorubens (vermillion snapper),
Hyporthodus flavolimbatus (yellowedge grouper), Sciaenops ocellatus (red drum),
Scomberomorus cavalla (king mackerel), and Scomberomorus maculatus (Atlantic Spanish
mackerel).


Propeller scarring hot spot analysis and behavior change/social marketing campaign for Tampa Bay

Presenter: Brendon Kendall *
Institution: University of Florida
Coauthors:
Quenton Tuckett | University of Florida
Abstract:
Seagrass meadows are highly productive critical habitats that provide a variety of ecosystem services. However, because seagrass meadows are found in shallow coastal areas, they are particularly vulnerable to degradation via anthropogenic activity. This is especially true of the large and growing human population of the Tampa Bay area, a region that relies heavily on coastal ecosystems for food, recreation, and tourism. A primary example of anthropogenic disturbance of seagrass ecosystems is boat propeller scarring. This occurs when boaters motor through water too shallow for their vessel. Restoration of seagrass can be expensive and time-consuming, it is thus recommended that more emphasis be placed on the prevention of propeller scarring. Seagrass scarring is a major issue in Florida and a recent machine learning mapping approach identified one propeller scar for every XX registered boats in counties bordering Tampa Bay. If solvable, this problem must be tackled with targeted education and outreach. Our main objective was to first identify angler Knowledge, Attitudes, and Practices (KAPs) through surveys. These KAP surveys allow us to identify knowledge gaps and behavioral patterns that can be used to identify where to spend resources on outreach. As anglers are a large and important user group in Tampa Bay, we sent out a standardized survey to Tampa Bay citizens with a fishing license. The results of the survey were used to curate a marketing and outreach campaign that included attending local science festivals, creating a billboard advertising the project, constructing signs at public boat ramps providing information on safe boating techniques, and interviewing with local newspapers to discuss the objectives of the project. A post-survey will be sent out to the same citizens to measure the effectiveness of the outreach campaign. Analysis of the post-survey will inform us on future possibilities to further expand the outreach campaign.


Optimizing commercial culture practices of Amphiprion ocellaris: minimizing deformities, improving egg handling, larval rearing practices, and juvenile growout to optimize profitability

Presenter: Brittney Lacy She/Her *
Institution: University of Florida Tropical Aquaculture Lab
Coauthors:
Casey Murray | University of Florida Tropical Aquaculture Lab
Andrew Ropicki | University of Florida Food and Resource Economics
Andrew Rhyne | Roger Williams University Center for Economic and Environmental Development
Christopher Martyniuk | University of Florida Center for Environmental and Human Toxicology
Matthew DiMaggio | University of Florida Tropical Aquaculture Lab
Abstract:
Clownfish (Amphiprion ocellaris) are a charismatic and popular marine fish in the aquarium trade and are a major contributor to the profits of marine ornamental fish farms. Challenges still arise in A. ocellaris aquaculture including, but not limited to, bottlenecks in broodstock spawning, larval rearing, juvenile growout, and prevalence of deformed offspring. Furthermore, formal research into A. ocellaris culture is sparse, leaving major data gaps. This project will address these gaps by 1) optimizing protocols for egg handling, larval rearing, juvenile growout, 2) reducing or eliminating live feeds, 3) identifying factors that influence development of deformities in larval and juveniles, 4) conducting economic analysis to determine effects of refined culture protocols on profitability, 5) characterizing clownfish perceptions and purchasing preferences, and 6) disseminating research findings to academics, extension personnel, and industry stakeholders through public workshops and other means. This project will study the effects of broodstock nutrition on larval quality through diet trials of common commercial diets followed by the analysis of fatty acid profiles of resulting spawns. Hatched larvae will undergo diet trials and larval quality will be assessed via RNA/DNA ratios and cortisol analysis via enzyme-linked immunosorbent assays (ELISAs). After 120 days, juveniles will be assessed for growth, survival, and presence of deformities. Types of deformities will be characterized through nano-CT and transcriptomics will be used to determine underlying physiological processes influencing the occurrence of deformities. Additionally, an economic analysis will be conducted to understand profit potential for new production strategies.


Bass Club Tournament Livewell Management: Participants Weigh-In

Presenter: Ted Lange
Institution: FL Fish and Wildlife Conservation Commission
Abstract:
The first of many catch and release bass tournament in Florida was held on Lake Kissimmee by the Bass Anglers Sportsman Society (BASS) in 1972. The Florida Fish and Wildlife Conservation Commission (FWC) instituted a permitting system for competitive black bass tournaments in 1975 to determine the need for regulations. The permitting system was discontinued in 1982 after it was concluded that competitive angling had little effect on bass populations. A second tournament permitting system began in 1992, concurrent with a change in the statewide daily bag and size limits for black bass. FWC again required catch data and results indicated minimal impacts on bass fisheries. Since that time, permitted bass tournament participants have been exempt from bass size regulations on most public waters. In 2011, the Black Bass Management Plan called for FWC to cooperate with the bass tournament industry and citizens to effectively manage bass tournaments to minimize negative perceptions. Survey results indicated that many anglers believe tournaments are good for bass fishing by promoting fishing, organizing anglers, and teaching ethics. Many were also concerned with tournament impacts such as crowding at boat ramps, angler ethics, and mortality. Because tournaments are “catch and release”, BASS and FWC provide guidance to tournament anglers with the Keeping Bass Alive (KBA) guidebook. KBA provides best management practices to increase the likelihood of bass surviving tournaments which in-turn protects the resource and projects a positive image of the sport. We worked directly with small club tournaments to assess knowledge of and adherence to KBA practices. We focused on one important area of KBA by monitoring livewell management practices and conditions during summer tournaments. A high degree of club angler participation was critical to our success in collecting Florida specific data to assess whether anglers were aware of KBA management practices and utilized them during summer when bass mortality is the highest. We will describe the benefits and challenges of working directly with club anglers to understand their behaviors with the goal influencing their success in releasing bass to be caught another day.


Acoustic telemetry, respirometry and biomechanics of reveal movement energetics of red drum (Sciaenops ocellatus) in Saint Augustine, FL

Presenter: James Liao
Institution: University of Florida
Whitney Lab for Marine Bioscience
Coauthors:
Esra Goturk | UF
Brendan Gibbs | UF
Clark Morgan | FAU
Abstract:
Locomotory performance is intimately tied to the physical properties of an environment. This is especially relevant for fish as fluids moving over the physical environment can create complex flow regimes. Despite this, swimming performance has largely been analyzed in uniform flow which may not be consistent with the conditions that an animal evolved in. This study set out to determine how movement through ecological flows changes fish swimming. Acoustic telemetry of a local marine species (Sciaenops ocellatus; n=43) was used to inform us the conditions in which to test swimming performance in the lab. Tagging data revealed a majority of fish populated areas near intracoastal inlets characterized by oyster reef and mangrove habitats. Since inlets are dynamic tidal environments with flow velocity fluctuations (20cm/s-120 cm/s), we tested swimming kinematics and energetics (n=5; 37.7 ± 1.3cm) under three relevant flow speeds: 22cm/s, 61cm/s and 100cm/s. Each flow speed was tested under three conditions: in uniform flow, behind a 2-D bluff body (5cm cylinder) to simulate movement through mangroves and behind a 3-D bluff body (10cm x 10cm mound) to simulate movement around rocks and oyster beds. Kinematic analysis was done through DeepLabCut which allows midlines to be reconstructed from a single trained neural network. It was found that the turbulent environments created by our bluff body treatments altered swimming kinematics compared to uniform flow. For example at 100cm/s, tailbeat frequency (Hz) behind a bluff body (cylinder= 15.99 ± 0.34; mound=14.728 ± 0.39) was significantly lower than in uniform flow (23.65 ± 0.35). We also found that swimming in unsteady flows drastically lowered energetics (At 100cm/s; laminar MO2=372.6; cylinder MO2=68.1; mound MO2=94.4). Our data suggests that testing performance limits alone is not sufficient to understand how animals move and an ecological lens must be considered when analyzing locomotory performance.


Iconic Trophy Bass- how FWC uses citizen-scientist-data to document, promote, and manage the biggest Largemouth Bass in Florida

Presenter: Summer Lindelien
Institution: Florida Fish and Wildlife Conservation Commission (FWC)
Abstract:
Florida is an iconic place for bass fishing, as anglers can fish for and catch bass weighing more than eight pounds in most locations with freshwater. Besides Florida’s expansive freshwater resources, our bass fisheries are buoyed by the distinct genetic character of Florida Bass, which can allow them to outgrow Largemouth Bass. Bass that grow over eight pounds are often referred to as trophy bass. Anglers have vested interest in traveling to and around Florida seeking to catch these rare specimens, and collecting information about the biggest bass is important to fishery scientists. Trophy bass are highly important based on the many stakeholders ranging from the public to researchers at universities who contributed to the Florida Fish and Wildlife Conservation Commission’s Black Bass Management Plan (2010 to 2030). As a direct result, in 2012, the Florida Fish and Wildlife Conservation Commission (FWC) created a documentation program that enables anglers to become citizen-scientists and contribute catch information about bass weighing eight pounds or heavier. This angler-recognition and trophy-bass conservation program is called TrophyCatch which is now in its eleventh season. Citizen-scientists have provided over 13,500 catches to the program which is about a tenfold increase over what FWC biologists have encountered during directed sampling over the same span. The expansive TrophyCatch data have stemmed numerous research projects to inform management. Recently, the FWC fisheries scientists implemented the Florida Trophy Bass Project. This project further focuses on the process of documenting, promoting, and managing Florida’s trophy bass. Using TrophyCatch and additional communication with the public to document and help with research on big bass, developing attention-grabbing promotions, and managing water bodies for trophy bass through regulation changes, supplemental forage, small-fish removals, as well as other strategies, we will ensure that Florida remains the “Bass Fishing Capital of the World”. We demonstrate how working with the public has vastly increased our means for data collection and enhanced the research and management of trophy bass in Florida.


Evidence of ontogenetic partitioning of restored coastal habitat by a generalist sportfish

Presenter: Jennifer Loch
Institution: University of Central Florida
Coauthors:
Geoffrey Cook | University of Central Florida
Abstract:
Coastal and estuarine habitats that provide crucial nursery areas for many economically and ecologically important fish species are in decline. Restoration of benthic habitats can improve fish populations, biomass, and feeding opportunities, but there is limited research on how restoration impacts growth and survival with ontogeny. To address this knowledge gap, here we examine the biometrics (size, biomass, body condition), recruitment, and trophic shifts of the sportfish Mangrove Snapper (Lutjanus griseus) at restored oyster reefs and stabilized living shorelines to better understand how fish use restored habitats as they grow. Biomass and body condition of juveniles and subadults and recruitment of L. griseus, at restored/stabilized habitats was similar, and in some cases greater than natural habitat, correlating with benthic habitat, reef location, and lunar phase at oyster reefs. Living shorelines exhibited greater recruitment potential, while oyster reefs supported more juveniles and subadults, as evidenced by differences in fish size and biomass between habitats. Dietary overlap implies subadult L. griseus likely foraged across habitats more than juveniles, while there was greater diet similarity within habitats. Further, ontogenetic shifts also occurred within oyster reef habitats, highlighting the importance of quality habitat to support various sportfish life stages, which can be achieved through restoration. These findings suggest life history attributes can be indicators of habitat restoration success, and specifically provide actionable science to guide the development of more effective strategies for restoring inshore nursery habitats and thus augment production of offshore reef fisheries.


Comparing machine learning to ratio-based estimates of protected species bycatch

Presenter: Christopher Long
Institution: Fisheries and Aquatic Sciences
School of Forest
Fisheries
and Geomatic Sciences
University of Florida
Coauthors:
Robert Ahrens | NOAA Pacific Islands Fisheries Science Center
Zachary Siders | Fisheries and Aquatic Sciences, School of Forest, Fisheries, and Geomatic Sciences, University of Florida
Abstract:
Methods for estimating total protected species bycatch typically extrapolate solely from temporal sampling coverage, which may not be appropriate for these inherently rare events and fails to take into account spatial variability in the bycatch risk. As these bycatch estimates are directly used to authorize take of protected species under the Endangered Species Act, it is critical to account for the sources of variability in bycatch risk. We estimated protected species bycatch by training Ensemble Random Forests (ERFs) using bycatch data of three protected species recorded by at-sea observers with 100% coverage of the Hawaii shallow-set pelagic longline (SSLL) fishery using 26 oceanographic covariates. From 2005-2021, the SSLL fishery made 18,988 sets with 639 sets interacting with Oceanic Whitetip Sharks, 190 with Loggerhead Sea Turtles, and 102 with Leatherback Sea Turtles. We then predicted bycatch for 2021 SSLL sets at simulated coverage levels of 20-80% and adjusted these predictions using known Type 1 and Type 2 error rates. We compared these ERF-derived estimates to those produced using a ratio-based estimator of bycatch. In 2021, the Oceanic Whitetip Shark estimates closely matched the actual value of 28 interactions with a mean prediction of 27.9 interactions (SD: 3.7). Likely as a result of very low bycatch rates, the Loggerhead (mean = 8.18 sets, actual = 14) and Leatherback (mean = 4.59, actual = 3) estimates were biased. However, by accounting for space, mean ERF estimates for total bycatch were substantially more precise than those produced by ratio-based estimators. The accuracy of using ERF bycatch estimation largely depends on the efficacy of accounting for Type 1 and Type 2 error and we continue to test the method using different years and simulated data.


Using a spatiotemporal model to create a standardized index of oyster abundance in Apalachicola Bay, FL

Presenter: Gabrielle Love she/her
Institution: University of Florida
School of Forest
Fisheries
and Geomatics Sciences
Coauthors:
Ed Camp | University of Florida, School of Forest, Fisheries, and Geomatics Sciences
Abstract:
The major collapse of the oyster fishery in Apalachicola Bay, FL has sparked great interest in understanding both the current and past states of this oyster population. Previous works have created abundance indices demonstrating the decline in oyster landings and live oysters using fisheries-dependent and fisheries-independent monitoring, but these indices have not incorporated spatial differences in abundance within the bay to illustrate the standardized, bay-wide oyster abundance through time. We used long-term fisheries-independent monitoring data with a spatiotemporal generalized linear mixed model and to create a spatially standardized index of relative oyster abundance in Apalachicola Bay from 1982 to 2021. We demonstrated the spatial and temporal effects on oyster abundance across the bay and across years, representing the contributions of specific oyster bars to estimates of population abundance. Our results illustrate the oyster population collapse and state of the current population while identifying certain oyster bars as potential high-value targets of restoration efforts.


Combing the Desert: Long-lingering effects of Post-Hurricane Vegetation Loss on Central Florida Lakes

Presenter: Earl Lundy
Institution: Florida Fish and Wildlife Conservation Commission
Coauthors:
Susanna Harrison | FL FWC
Jay Holder | FL FWC
Abstract:
In most Florida lakes, aquatic vegetation is present, often abundant, and the basis of a healthy ecosystem. After Hurricane Irma impacted the St. Johns River basin in 2017, large patches of both submersed and emergent aquatic vegetation were removed from the St. Johns River and its attendant lakes. A similar pattern was observed in 2004 when Hurricanes Charley, Frances, and Jean impacted the St. Johns River basinHowever, after these events the aquatic vegetation returned within one to three years. After the impacts of Irma in 2017, the vegetation has not returned, and what little SAV that was present immediately after the hurricane has vanished. As aquatic vegetation is an important refugia for forage species and juvenile sportfish, the loss of this habitat has had predictably deleterious effects. As a result of this, we have observed shifts in the fish communities and fisheries on middle St. Johns River lakes. Community sampling has shown lower catch rates in terms of numbers of fish collected on lakes Crescent, George, and Monroe, and lower biomass catch rates on Crescent Lake and Lake Monroe. Our data have indicated an increase in rough fish contribution to the community makeup and a decline in forage fishes in all three lakes during fall community sampling. We have also observed an increase in sunfishes Lepomis spp. for Crescent Lake and Lake George, driven largely by an increase in Bluegill. Spring Largemouth Bass catch rates have also declined on all three lakes. Creel data for Lake George have indicated a sharp drop in both total angling effort and Largemouth Bass effort since Hurricane Irma. These changes have had an impact on local economies, as lower angler effort has lead to decreased freshwater angling tourism and attendant revenues for fish camps and fishing-related expenditures.


Stakeholder Preferences and Perceptions for Oyster Restoration in Apalachicola Bay, Florida

Presenter: Elizabeth Mansfield she/her
Institution: Florida State University – Coastal & Marine Lab
Coauthors:
Sarah Lester | Florida State University
Andrew Rassweiler | Florida State University
Sandra Brooke | Florida State University – Coastal & Marine LAb
Abstract:
Oysters historically played a huge role within the economic and cultural landscape of the Apalachicola Bay, providing a suite of ecosystem services. Yet the fishery is closed until the end of 2025 due to an array of stressors which led to a drastic population decline of the species. As such, the restoration and recovery of oysters in the Apalachicola Bay is a priority for many stakeholders. However, the priorities for oyster restoration can vary among user groups based on knowledge and preferences for different oyster ecosystem services. This study aims to chronicle the variation in restoration priorities and perceived value of oyster reefs among seafood industry stakeholders of the Apalachicola Bay. Utilizing semi-structured interviews, we are speaking with community members who relied upon, interacted with, or benefited from the oyster population in a variety of ways. We find that stakeholder priorities are most often tied to the reopening of the fishery and the subsequent revitalization of the economy which is closely tied to the fishery. Furthermore, results indicate that stakeholders view the need for placement of reef material on degraded historical bars as a high priority for restoration success. This work will provide social context and feedback to decision-makers and researchers related to restoration initiatives in the Bay, and emphasizes the importance of including user experiences and opinions in the study and restoration of coupled human-natural systems.


Effects of Algal Manipulations on the Survival, Growth, and Feeding Incidence of Larval Neocirrhites armatus

Presenter: Olivia Markham she/her/hers *
Institution: University of Florida
Coauthors:
Casey Murray | University of Florida
Sarah Hutchins | University of Florida
Matthew DiMaggio | University of Florida
Abstract:
The flame hawkfish (Neocirrhites armatus) is a marine ornamental fish endemic to the Indo-Pacific and is popular in the aquarium trade due to its bright coloration, small size, and behavior. Due to their popularity, captive rearing of hawkfish is of great interest, but is limited by difficulties in broodstock spawning and larval rearing. The stage of “first-feeding” at 3 DPH, where endogenous reserves are exhausted and the larvae must switch to exogenous feeding, is critical for development and survival. Mass mortality of larvae is common during this period from lack of appropriate nutrition. Attempts to culture these larvae have been successful until 12 DPH, with significant mortality observed at 10 DPH. Mortality at this developmental stage could be due to other developmental bottlenecks, such as swim bladder inflation or notochord flexion, which occur at 7 DPH and 9 DPH, respectively.

There is no current information on larval rearing of N. armatus and initial experiments evaluated effects of environmental conditions on survival, growth, and feeding incidence from 0 – 5 DPH. The effects of algal density (150,000 – 600,000 cells mL-1) were evaluated for larvae at 3 DPH. Results of this experiment showed significantly higher survival and feeding incidence at 150,000 cells mL-1 compared to other treatments. Experiments evaluating the effects of algae species are currently underway, comparing Tisochrysis lutea and Nannochloropsis oculata. Other environmental conditions of interest include copepod species, copepod density, and prey type. These experiments will all focus on improving survival at first feeding. Future experiments may focus on bottlenecks in production at 10 DPH. The development of early larviculture protocols for N. armatus will provide critical information necessary for commercialization of this species.


Manipulating Environmental Parameters to Improve Survival, Growth, and Feeding Incidence of Larval Dascyllus Auripinnis

Presenter: Olivia Markham she/her/hers *
Institution: University of Florida
Coauthors:
Casey Murray | University of Florida
Sarah Hutchins | University of Florida
Matthew DiMaggio | University of Florida
Abstract:
The golden domino damselfish (Dascyllus auripinnis) is a popular ornamental species and has encouraging attributes for their successful aquaculture. Significant mortality from starvation is observed during the “first feeding” period, where larvae transition from endogenous to exogenous feeding. Additionally, environmental conditions can influence the identification and capture of prey items. Ideal conditions for growth are species-specific and improvements in culture protocols would help to facilitate the commercialization of this species.

To assess the effects of various rearing conditions on the culture of damselfish, manipulations of algae density, copepod species, copepod density, prey type, and photoperiod were evaluated at 0 – 5 days post hatch (DPH), with the duration dependent on the parameter. Results from the algal density experiment indicated the greatest survival in the microalgal density 150,000 cells mL-1 of Tisochrysis lutea and in the control. Feeding larvae Parvocalanus crassirostris resulted in significantly higher feeding incidence over Oithona calcarva. Using these results, P. crassirostris was used for testing copepod density, resulting in greater survival in the 5 copepods mL-1 and 10 copepods mL-1 treatments. The prey type experiment tested the inclusion of rotifers at first feeding and resulted in a significantly higher survival in larvae that were fed a 50/50 mix of rotifers and copepods, as well as an equally high survival in the diet of exclusively copepods. A photoperiod of 24-hour light had a significantly higher larval survival and initial feeding incidence. These results contribute to the development of commercial production techniques for D. auripinnis and can provide important insights into larval feeding behavior.


Utilizing radio telemetry to investigate the survival and behavior of Grass Carp stocked in Florida Lakes.

Presenter: Logan Masterson *
Institution: Florida Fish & Wildlife Conservation Commission/University of Florida
Coauthors:
Brandon Thompson | Florida Fish & Wildlife Conservation Commission
Andrew Carlson | University of Florida
Abstract:
Hydrilla, Hydrilla verticillata, a submersed aquatic plant native to Southeast Asia, was introduced into Florida in the 1950s. Since, its invasive characteristics have presented many challenges for plant managers. Managers are frequently confronted with meeting diverse stakeholder desires to control an aggressive exotic plant, while also considering the optimal control methods using a limited budget. Stocking Grass Carp has been used effectively in small, enclosed systems as a cost-effective alternative to extensive chemical herbicide treatment. Managers currently use Grass Carp in smaller enclosed waterbodies like private ponds and small lakes. Managers often do not use Grass Carp as a management technique for larger connected systems like the Harris Chain of Lakes. This is because stocking Grass carp in large, open systems can have unintended impacts to native vegetation if overstocked or if emigration rates are high. To make informed decisions on integrating Grass Carp stocking in large open systems, it’s important to understand the dispersal, habitat preference, survival, and emigration rates for stocked Grass Carp. In this study, we have begun to use radio telemetry to assess Grass Carp behavior and survival at several central Florida lakes. In the first year, we found that stocked Grass Carp will quickly disperse from the stocking site, and distribute readily throughout the primary hydrilla infestations, indicating their initial effectiveness as a biological control tool. Passive datalogging receivers were also positioned to identify any emigration from the stocked lake, which we have so far witnessed in low proportions. In the second year of this study, we tagged Grass Carp in two open systems, and modified tagging strategies in an effort to better provide managers with reliable estimates of survival and emigration rates.


Provision of oyster reef habitat by the Pervious Oyster Shell Habitat (POSH) Along Two Energetic Shorelines in Northeast Florida

Presenter: Hunter Mathews *
Institution: University of North Florida
Coauthors:
Kelly Smith | University of North Florida
Abstract:
The Pervious Oyster Shell Habitat (POSH) is a novel oyster reef restoration device, composed of oyster shell bound by a thin layer of Portland cement, into a mound. The POSH is environmentally friendly and contains ample vertical relief and interstitial space for habitat provision. Here, we have assessed the POSH for major metrics of oyster reef restoration success, compared to the oyster Reef BallTM, a similar and popular method for restoration. Structures were deployed along Kingsley Plantation (Timucuan NP) and Wright’s Landing (GTMNERR) in northeast Florida in the summer of 2021. After a year in situ, oyster and barnacle densities and oyster size distributions on artificial reefs were assessed. The POSH recruited significantly greater oyster densities at both sites, while barnacle densities were low and highly variable. Utilization of the artificial reefs by fish and mobile decapod crustaceans was assessed using 2 m2 bottomless lift nets in summer, fall (2022), and winter (2023). The catch efficiency of the bottomless lift nets was assessed at Wright’s Landing using Palaemonetes spp. dyed with methyl blue, and ranged from (25-83%). Fish densities and diversity did not differ between the structures, or a natural oyster reef control, throughout the year. Crustacean densities differed significantly throughout the year at the Kingsley Plantation site and in summer at the Wright’s Landing site, with similar diversity. Communities using the POSH, Oyster Ball, and natural reef control were similar throughout the study period. The POSH was preferentially used by crustaceans and resident demersal fish, while a greater variety of structure-oriented transient fish were caught on the Oyster Ball. Our results show that the POSH can be an optimal substrate for oyster recruitment and nekton habitat in high-energy systems and highlight the importance of increased complexity for oyster reef habitat provision.


Movement and habitat use of juvenile Bull Sharks Carcharhinus leucas in an estuarine nursery system

Presenter: Peyton McCain she/her/hers *
Institution: Florida Southern College
Coauthors:
Gabriel Langford | Florida Southern College
Allison Durland Donahou | Florida Southern College
Abstract:
The Alafia River Estuary (ARE), Florida, houses many species of elasmobranchs, including the Bull Shark Carcharhinus leucas. Bull Sharks use estuarine habitats as pupping grounds and nurseries. Tampa Bay and Charlotte Harbor are suspected to host nursery habitats for at least 11 different species of shark. Despite this knowledge, research into the use of the ARE as a nursery for Bull Sharks has been limited. In this study, 18 juvenile Bull Sharks were tracked through the ARE system over the course of 2 years, using passive acoustic telemetry. These movements were used to find patterns in overall activity and total distance traveled per size class, as well as patterns of movement between the six different receiver locations throughout the year. A total of 68 Bull Sharks were collected using gill nets over the course of the two-year study, with ten being classified as neonate (fully open or partially healed umbilical wound), 45 as young of year (≤90 cm TL), and 13 as juvenile (>90 cm TL). The overall CPUE was 0.64 sharks/net. This analysis is part of the first long-term study on Bull Shark nursery habitats in the ARE, and hopes to identify important estuarine areas and outline the importance of the Eastern Gulf of Mexico in the reproduction of Bull Sharks.


Fish assemblages on offshore sand shoals and potential impacts due to dredging

Presenter: Debra Murie she/her
Institution: School of Forest
Fisheries
and Geomatics Sciences
University of Florida
Coauthors:
Geoff Smith | University of Florida
Abstract:
Sand shoals are relatively common features along the eastern US seaboard that can provide some vertical structure in a landscape of little to no physical relief. For fishes, these shoals provide physical structure that potentially enhances foraging, protection from predators, spawning, and potential nursery areas for recruitment, all functions that are associated with the definition of Essential Fish Habitat (EFH). However, sand shoals are also dredged and the sand used for beach renourishment following major hurricane activity, such as for Hurricane Sandy in 2012. The overall goal of this study was to describe and quantify the fish diversity, abundance, biomass, and assemblages associated with sand shoals off the east coast of Florida on a spatiotemporal basis in relation to sand dredging events. Our study employed a Beyond-BACI design, including multiple reference shoals (Canaveral Shoal II, Chester, and Bull Shoals), an impact (dredged) shoal (Canaveral Shoal II Borrow Area), and temporal sampling before and after the dredging events spanning from Fall 2013 through Summer 2019 using standardized trawl surveys. Overall, median fish abundance and biomass differed among all shoals with season the major factor rather than dredging activity. Fish abundance and biomass was greater during the Fall, and 2-3 times greater during night compared to daytime sampling. Diversity was greatest during Spring through Fall and was lowest during the Winter. Multivariate analysis of fish assemblages also indicated that season explained the greatest amount of variation. Sand shoals off the east coast of Florida are dynamic systems with natural temporal variation in fish assemblages exceeding any impact due to dredging alone.


Minimizing the use of Artemia during larval production of Betta splendens

Presenter: Casey Murray she/her *
Institution: University of Florida
Coauthors:
Olivia Markham | University of Florida
Eva Domas | University of Florida
Matthew DiMaggio | University of Florida
Abstract:
Betta splendens, also known as the Siamese fighting fish, is an anabantoid native to Southeast Asia and is among the top ten freshwater ornamental fish species imported into the USA for the aquarium trade. Although B. splendens is a staple in the ornamental aquaculture industry, the larval production process continues to rely heavily on the use of Artemia nauplii. Digestive physiology data can be used to minimize the use of costly live feeds during larval production by indicating when larvae can digest complex feeds like microdiets (MDs). A 30-day trial was conducted to determine the timing of the maturation of the digestive tract. Standard microplate assays were conducted to quantify pepsin, trypsin, and lipase activities and histology was used to describe digestive tract morphology. Pepsin activity and the development of gastric glands indicated the presence of a functional stomach between 15-18 DPH (days post-hatch). Next, a 42-day dietetics trial was conducted to determine which of three commercially available MDs best promoted growth and survival in larval B. splendens compared to an Artemia reference diet. Survival was statistically similar for larvae fed Gemma Micro compared to the Artemia nauplii reference diet and all MD treatments yielded significantly higher growth compared with the reference diet. Finally, a 25-day weaning trial was conducted where MD was introduced at three timepoints surrounding the development of the digestive tract. Larvae were subjected to one of five treatments: Artemia reference diet, MD from first-feeding, or MD introduction at 12, 15, or 18 DPH. MD introduction at 15 and 18 DPH yielded similar survival and growth compared to the Artemia reference diet. MD from first-feeding yielded statistically lower survival and growth compared to all other treatments. These results suggest that B. splendens can transition to a MD as early as 15 DPH without sacrificing growth or survival.


Histological and physiological characterization of the digestive ontogeny of larval clownfish Amphiprion ocellaris

Presenter: Casey Murray she/her *
Institution: University of Florida
Coauthors:
Olivia Markham | University of Florida
Sarah Hutchins | University of Florida
Matthew DiMaggio | University of Florida
Abstract:
Clownfish (Amphiprion ocellaris) are the most recognizable and popular marine aquarium fish and are a key commodity for marine ornamental fish producers. Although these fish have been raised in captivity for decades, producers are still experiencing issues regarding larval survival, reliance on live feeds, and post-larval deformities. To improve the culture process, the ontogeny of larval development and digestive capacity, namely stomach development, was examined. Stomach functionality indicates the capacity of larvae to better digest and utilize microdiets (MDs) that can be used to replace costly live feeds during larval rearing. The morphological development, digestive enzyme ontogeny, and digestive tract development of A. ocellaris was examined in a 16-day trial. Standard microplate assays were conducted to quantify the activity of trypsin, lipase, and acid protease enzymes from 24 hours before hatching to 15 days post hatch (DPH). Histology was used to visualize morphological changes in the digestive tract throughout the larval period. At hatching, A. ocellaris has functional eyes, an open mouth, and a coiled, differentiated digestive tract. Gastric gland formation was observed at 6 DPH, with stomach functionality occurring between 7 – 9 DPH, indicated by gastric gland proliferation and an increase in acid protease activity. Lipase and trypsin activities were detectable before hatching and increased significantly after 6 DPH. These data were used to design a weaning trial to transition larvae from live feeds to MD without affecting larval growth or survival. Overall, understanding larval digestive ontogeny can aid in streamlining larval rearing and reducing reliance on costly live feeds.


Diel or no diel: Benthic fish assemblages on gravel bars vary with depth and time of day

Presenter: Chelsea myles-Mcburney
Institution: Florida Fish and Wildlife
Coauthors:
Jason O’Connor | Florida Fish and Wildlife
Abstract:
Gravel Bars are dynamic riverine habitats that harbor a diversity of organisms and contribute unique ecological values within the active channel of rivers (Zeng 2015). Little directed sampling efforts have been conducted on gravel and pebble habitats for fishes that have an obligate relationship to these habitats. Furthermore, few studies have documented entire fish assemblages and their diel and depth patterns on gravel bars. In Florida, gravel and pebble substrate are almost found exclusively in the upper reaches of the Escambia River. The Escambia River drainage supports the richest assemblage of fish species compared to any other Florida stream with 85 native freshwater species recorded along with several rare and threatened species (Boning 2007). In order to effectively sample small benthic fishes, a Siamese trawl with a dual-mesh bag was selected to sample gravel bar habitat. The purpose of this study was to examine fish assemblages across gravel bar habitats within the Escambia River. Furthermore, determining if changes in fish assemblage differ among times of day, depths, and seasons. Over 66 trawls, 1,130 individuals, comprised of 30 species were collected. Overall catch composition was significantly different among day and night trawls (R = 0.328, p < 0.001), shallow and deep trawls (R = 0.142, p = 0.038) and among trawls conducted at different sites (R = 0.362, p < 0.001). By utilizing different sampling techniques, such as trawling, we can determine the most effective species-targeted surveys along with collecting the most comprehensive data on fish assemblages on gravel habitat within the Escambia River.


Assessing Catch Efficiency of Bottomless Lift Nets on Artificial Oyster Reef Structures

Presenter: Gabrielle Nelson She/her *
Institution: University of North Florida
Abstract:
This study aims to test bottomless lift nets’ efficiency on two different oyster reef restoration methods at Wright’s Landing. Grass shrimp, Palaemonetes, were gathered from Guana Lake, dyed, and released into the raised lift nets. Dip nets were used to sweep around the enclosed area and recapture the marked shrimp. Clearly marked shrimp were recorded and released. Shrimp that could not be clearly identified as marked were taken back to the lab to be inspected under a microscope. Once the data was consolidated from the field and lab analysis, the recapture rates for each of the treatments were calculated. The data was tested for normality using a Ryan-Joiner test. A single-factor ANOVA was conducted and found that there was no significant difference in catch efficiency of the two treatments.


Spotted Bullhead Population Status: A Tale of Two Regions?

Presenter: Jason O’Connor he/him
Institution: Florida Fish and Wildlife Conservation Commission
Coauthors:
Chris Anderson | FWC
Travis Tuten | FWC
Josh Wilsey | FWC
Brandon Barthel | FWC
Abstract:
Spotted Bullhead Ameiurus serracanthus are a small-bodied ictalurid, which generally occupy larger rivers with moderate flow and rocky habitat. They are considered a species of greatest conservation need in Florida because they occupy a small range, which is mostly restricted to watersheds along Florida’s gulf coast. There is evidence that interactions with non-native Flathead Catfish in some panhandle drainages has resulted in declines in abundance of Spotted Bullhead. Despite known conservation threats, there has been little recent directed effort to quantify patterns of abundance across the species range and catfish species are poorly detected with routine monitoring protocols. We sought to compare the relative abundance of Spotted Bullhead across peninsular and panhandle drainages, and in relation to the occurrence and abundance of Flathead Catfish. We used low-pulse electrofishing to target catfish. Surveys were conducted in fall of 2021 and spring of 2022. Spotted Bullhead relative abundance was highest in the southern Withlacoochee River (2.3 ± 0.6 fish/min). Spotted Bullhead were the most abundant catfish species collected in peninsular drainages. Flathead catfish was the most abundant ictalurid collected in all panhandle drainages (mean cpue = 0.7 ± 0.3 fish/min), while Spotted Bullhead were rare in these drainages (mean cpue = 0.03 ± 0.03 fish/min). Spotted Bullhead were not detected in the Yellow River, nor in any of the minor Gulf drainages between the Ochlocknee and Suwanee River. These results suggest that panhandle populations are persisting at lower abundances than peninsular populations and this is pattern is correlated with the occurrence of Flathead Catfish. However, this pattern is also confounded with major water quality and habitat differences among these watersheds. Further study is necessary to assess whether mortality rates vary among peninsular and panhandle populations, and may elucidate whether conservation action is warranted.


Estimating the influence of modeled oceanographic variables on juvenile snapper abundance in the Middle Florida Keys

Presenter: Jack Olson He/Him
Institution: Florida Fish and Wildlife Conservation Commission
Coauthors:
Ariel Tobin | Florida Fish and Wildlife Conservation Commission
Alejandro Acosta | Florida Fish and Wildlife Conservation Commission
Abstract:
Pre-settlement oceanic conditions may affect the growth, survival, and dispersal of pelagic larval fish thus mediating recruitment rates and subsequent adult population dynamics. While it remains difficult to separate the effects of pre-settlement and post-settlement processes on recruitment, incorporating both types of variability into recruitment models has been shown to improve resulting indices. The motivation of this work was to refine existing recruitment indices for fishery-important species in the Middle Florida Keys by isolating and assessing the effects of oceanographic variables on post-settlement abundances. Between 2007 and 2019, juvenile fish surveys were conducted monthly in nearshore seagrass beds of the Middle Florida Keys using a 21.3 m center-bag seine. Here, we modeled the abundance of settlement stage snapper (total length <= 40mm) as a function of current speed, current direction, water temperature, and salinity produced by the Hybrid Coordinate Ocean Model (HYCOM). Preliminary results indicated that current speed and direction were the strongest predictors of recruitment. The strength and significance of predicted effects were dependent on both the offshore region and pre-settlement time period for which HYCOM variables were extracted. This work demonstrates an effort to complement fishery-independent monitoring with high resolution oceanographic data to provide updated recruitment information to fisheries managers in the Florida Keys.


Developing stereological methods to assess female reproductive condition for red drum (Sciaenops ocellatus) hatchery management

Presenter: Kaitlyn O’Neil *
Institution: Marine Fisheries Enhancement Center
Fish and Wildlife Research Institute
Florida Fish and Wildlife Conservation Commission
Apollo Beach
FL; Program in Fisheries and Aquatic Sciences
School of Forest
Fisheries
& Geomatics Sciences
University of Florida/IFAS
Gainesville
FL
Coauthors:
Josh Patterson | Program in Fisheries and Aquatic Sciences, School of Forest, Fisheries, & Geomatics Sciences, University of Florida/IFAS, Gainesville, FL
Jason Lemus | Marine Fisheries Enhancement Center, Fish and Wildlife Research Institute, Florida Fish and Wildlife Conservation Commission, Apollo Beach, FL
Sue Lowerre-Barbieri | Program in Fisheries and Aquatic Sciences, School of Forest, Fisheries, & Geomatics Sciences, University of Florida/IFAS, Gainesville, FL; Movement Ecology and Reproductive Resilience Lab, Fish and Wildlife Research Institute, Florida Fish and Wildlife Conservation Commission, St. Petersburg, FL
Abstract:
Research in developing new and innovative approaches to stock enhancement is essential to managing, conserving, and restoring marine sport fisheries. Red drum (Sciaenops ocellatus) is an iconic inshore sportfish species, with juveniles supporting a major recreational fishery. Substantial stock enhancement of such sportfish relies on the ability to optimize spawning of broodstock in captivity, among other processes. Improving identification of spawning conditions and optimizing spawning quality for both stock enhancement research and production requires accurate and succinct description of oocyte development in captive red drum as a reference. Oocyte biopsies during photothermal manipulation periods (regression/regeneration, development, and spawning) were collected with a 10-cm cannula (1.5-mm inner diameter polyethylene tubing) attached to a 5-cc syringe and preserved in Trump’s fixative for staining and histological analysis. Stereology is the science of quantifying structural features of an object (oocytes) from a two-dimensional surface (histological sections), which has been used in the past to accurately estimate fecundity of fishes. Oocyte stage densities were estimated, using assumption-based stereology, to measure oocyte development through these photothermal manipulation phases. Then, ovary statuses were assigned using currently accepted nomenclature based on trends in oocyte densities. This reference data and ovarian statuses can be used in the future to determine whether captive red drum are progressing normally.


A Synthesis of the Scientific Literature on Positive Density Dependence as a Possible Cause for Oyster Reef Collapse

Presenter: Chad Palmer He/Him *
Institution: University of Florida
Coauthors:
Ed Camp | University of Florida
Abstract:
Oyster reefs, both throughout Florida and around the globe, have been experiencing collapse which has resulted in an 85% decrease of oyster reef habitats worldwide. Many scientific studies have been undertaken to better understand the cause of this collapse and ensure better management of these ecologically and economically important ecosystems. While ecological misunderstanding is rarely the primary cause of insufficient natural resource management, it can result in such collapses as have been seen in oyster reefs. It is possible, given what we know about oyster as ecosystem engineers, that oyster population dynamics may include some positive density dependent mechanism, that may be driving sudden collapses in fished oyster populations. This study examines the current scientific literature regarding the collapse of oyster fisheries to determine whether evidence exists for positive density dependence as a driver of oyster fishery collapse and to determine best avenues for future research on positive density dependence in fished oyster populations.


Using long-term monitoring data to investigate estuarine metacommunities

Presenter: Jonathan Peake *
Institution: Florida Fish and Wildlife Conservation Commission
Coauthors:
Christopher Stallings | University of South Florida College of Marine Science
Abstract:
Community-level processes affect all levels of fisheries systems, from single stocks to ecosystems to global patterns of biodiversity. To date, much of the research in fisheries science has focused on a subset of these processes. Ecosystem models can integrate these processes to test hypotheses related to fishery stocks but often rely on simulated ecosystems based on parameters that are broad-stroke estimates for how these processes affect community assembly. Recent developments in joint species distribution modeling (JSDM) have allowed for more empirical investigations of the relative effects of local and regional factors that influence communities over space and time. The Fisheries-Independent Monitoring program of the Florida Fish and Wildlife Research Institute has collected almost 30 years of continuous community data across multiple Florida estuaries. This dataset provides a unique opportunity to investigate the processes affecting estuarine communities. Using the Hierarchical Modeling of Species Communities (HMSC; Ovaskainen et al. 2017) JSDM framework, I modeled the relative influences of habitat, species co-occurrence, spatial structure, and drift on sub-adult and adult fish communities in seven estuaries over a 25-year period spanning 1996-2020. Model fit varied across species but was generally highest in common species. Habitat accounted for the largest proportion of explained variability across most species, with different estuaries revealing differing strengths of habitat association. Species co-occurrence and spatial structure had relatively low but variable effects across species. The relatively high effect of habitat on species occurrence and abundance suggests that habitat preservation should continue to be a key focus of fisheries management in this area. By identifying the relative influences of local and regional factors affecting estuarine communities, we can better understand the major processes that influence the distribution and abundance of species. This can lead to better predictions of future stocks over changing conditions and improved future management of fisheries species.


Implementation of collaborative open science tools to improve engagement with the ecology of the Guana River Estuary

Presenter: Kristie Perez she/her *
Institution: School of Forest
Fisheries
and Geomatics Sciences
University of Florida
Coauthors:
Geraldine Klarenberg | gklarenberg@ufl.edu
Shirley Baker | sbaker25@ufl.edu
Nia Morales | n.morales@ufl.edu
Nikki Dix | nikki.dix@dep.state.fl.us
Abstract:
The Guana Tolomato Matanzas National Estuarine Research Reserve includes multiple water resources where physical access and data access is in demand by a variety of user groups. Further, the needs of these users extend beyond the information currently available. Funded by a Science Transfer Grant from the NERRS Science Collaborative, we are developing a web-based dashboard to provide access to ecological data sets and visualizations, expanding engagement to the local community This dashboard will serve as a connection between science, data, and people by employing and promoting the principles of open data and open science in an interactive and user-friendly way.

The initial phase has focused on understanding and documenting end-users’ needs: their expectations, technical requirements, and perspectives on the data. To date, this included brainstorming data needs in a virtual kick-off meeting, then, in an in-person collaborative workshop, prioritizing those and creating potential design mock-ups. Finally, an online snowball survey to further understand specific data uses and needs is being implemented. These activities were all conducted with a diverse group of local stakeholders (potential users). We recorded overlapping and diverging needs of the three (self-identified) user groups: community members (e.g., residents, volunteers), professionals (e.g., business owners, educators, resource managers) and researchers. The completion of this phase includes analysis of the data collected from the online survey and developing the initial framework for the dashboard using Shiny in R.

The findings to date have led the project implementation team to consider which needs overlap, and which diverge. In general, researchers’ needs are more raw data focused, while the community and professionals expressed the need for interpretive and illustrative data. The latter groups also expressed a desire for more interactive dashboard features (e.g., submitting pictures or information, contacting researchers). It is imperative that we understand the feasibility and applications of these features to ensure creation of a robust dashboard that engages the target users and meets the needs of the diverse surrounding community.


Integrating Management Objectives into Stocking Optimization

Presenter: Diana Perry she/her *
Institution: University of Florida
Coauthors:
Conor McGowan | Florida Cooperative Fish and Wildlife Research Unit
Edward Camp | University of Florida
Abstract:
Stock enhanced freshwater recreation fisheries require the efficient use of hatcheries to address ecosystem needs and stakeholder preferences. Due to limited hatchery space each rearing season and the diverse preferences of managers and stakeholders alike, it challenging to decide which species and sizes of fish to stocked. Each species and life stage reared requires a certain amount of space, time, and other resources. Managers must balance diverse stakeholder preferences, ecological needs, and hatchery constraints appropriately to successfully develop and maintain recreational fisheries. Efficiently delegating space in the hatchery can be optimized by addressing it as a knapsack problem—a combinatorial optimization problem that solves for the highest value attainable given a combination of weights and values of the possible stocking options within the constraints of the hatchery. By modeling the space required to rear each species and its value to the ecosystem and to stakeholder satisfaction, the knapsack optimization can deliver a solution that could result in high fishery management success given the parameters laid out by the state. We collaborated with Florida Fish and Wildlife Conservation Commission hatchery and stocking managers and researchers to identify rearing option weights based on the space required to rear each stocking option and values based on management preferences. We used data from a previous surveys on stocking preferences to determine angler stocking priorities. This optimization illustrates the impact of specific stocking options and the sensitivity to different types of manager and stakeholder preferences. This optimization could prove useful across other region or state stocking programs. Additionally, this optimization can increase transparent communication between fisheries and hatchery managers or between stakeholders and managers as well as contribute to increasingly informed hatchery decisions.


Calcein marking of Hogfish (Lachnolaimus maximus), a potential tool for future stock enhancement

Presenter: Brandon Ray *
Institution: Tropical Aquaculture Laboratory
University of Florida
1408 24th Street Southeast
Ruskin
Florida
33570 USA
Coauthors:
Casey Murray | Tropical Aquaculture Laboratory, University of Florida, 1408 24th Street Southeast, Ruskin, Florida, 33570 USA
Olivia Markham | Tropical Aquaculture Laboratory, University of Florida, 1408 24th Street Southeast, Ruskin, Florida, 33570 USA
Cortney Ohs | Indian River Research and Education Center, University of Florida, 2199 South Rock Road, Fort Pierce, Florida, 34945 USA
Joshua Patterson | The Florida Aquarium, Center for Conservation, 529 Estuary Shore Lane, Apollo Beach, Florida, 33572 USA
Angela Collins | Florida Sea Grant, University of Florida Institute of Food and Agricultural Sciences Extension, Manatee County Government, 1303 17th Street West, Palmetto, Florida, 34221 USA
Matthew DiMaggio | Tropical Aquaculture Laboratory, University of Florida, 1408 24th Street Southeast, Ruskin, Florida, 33570 USA
Abstract:
Hogfish (Lachnolaimus maximus), a large wrasse native to the western Atlantic, are a popular sport and food fish whose southern population have been experiencing overfishing for the past 30 years. Despite their popularity, interest in commercial culture has only recently emerged. Poorly defined culture methods persist as an impediment to potential restoration efforts with this species. Additionally, no information currently exists on effective marking procedures for hatchery produced hogfish. Feasibility of culture and potential stock enhancement is predicated on elucidation of effective protocols. To this end, we explored the efficacy of various protocols using Calcein as a marking agent for hogfish.

Calcein is a non-lethal, fluorescent, chemical marker that binds to the calcified structures in exposed animals. To assess its potential for use on hogfish, we used the osmotic induction method where animals were exposed to a hypersaline environment for 3.5 minutes prior to immersion in calcein for the same time, thereby resulting in calcein uptake and marking. We tested pre-treatment salinities of 32, 45, 60, and 75 g/L followed by a 3 g/L calcein exposure. A second experiment then tested calcein concentrations of 0, 1, 3, and 5 g/L using the salinity pretreatment that resulted in the brightest mark from the first experiment; only the highest saline and calcein concentrations showed significantly brighter marks than the weakest marked fish. These results identify baseline calcein marking protocols for use with hogfish. Further research into mark retention is warranted to evaluate the usefulness of this tool in potential stock enhancements efforts.


The Parasites of the Unwanted: Endoparasite Fauna of Mesopredatory Teleost Pelagic Longline Bycatch

Presenter: Alexander Rayburn He/Him *
Institution: Nova Southeastern University
Coauthors:
David Kerstetter | Nova Southeastern University
Christopher Blanar | Nova Southeastern University
Abstract:
The ecology of the mesopelagic zone is an understudied area of the open ocean, with few diet studies even for dominant fish species. Since endoparasites are generally transmitted trophically, descriptions of the parasite communities within fishes can often provide additional insights on food web interactions. This project assesses the endoparasite faunal community of mesopredatory mesopelagic teleosts to better understand mesopelagic food webs in the South Atlantic Bight. Fishes in the Families Alepisauridae (lancetfishes) and Gempylidae (snake mackerels) are frequent bycatch in the pelagic longline fishery targeting Swordfish Xiphias gladius and thunnid tunas yet the ecology of these mesopelagic species is poorly known. Whole fish specimens were collected onboard commercial vessels by observers, frozen, and examined in the laboratory. Of the 105 fishes examined to date, 95% were infected by at least one parasite taxon. Lancetfishes commonly hosted the cestode Pelichnibothrium speciosum (91% prevalence, n=33), and gempylids commonly hosted the nematode Anisakis sp. (88% prevalence, n=72). Lancetfishes are potentially a unique case due to their high rate of cannibalism (45%), which may allow for multiple developmental stages of P. speciosum to coexist in the same host. These co-occurring stages of cestode may help the worm to develop before entering the definitive host, Blue Shark Prionace glauca. Escolar (n=22) show a low infection intensity (7 per host) relative to other studied host species. For reference, Lancetfishes Alepisaurus spp. (n=27) have an infection intensity of 151 per host, Oilfish Ruvettus pretiosus (n=19) have an infection intensity of 122 per host, and other gempylids combined (n=33) have an infection intensity of 76 per host. The high infection intensities in Lancetfishes and Oilfish may indicate their role as intermediate hosts for parasites seen in apex predators targeted by the pelagic longline fishery.


Diversity patterns of subtropical fish assemblages on artificial and natural reefs in the eastern Gulf of Mexico.

Presenter: Michael Schram he/him/his *
Institution: Univ. of South Florida
College of Marine Science
Coauthors:
Christopher Stallings | Univ. of South Florida, College of Marine Science
Abstract:
Identifying species assemblage patterns is a critical first step for understanding the processes and mechanisms that drive community structure and helps to inform restoration, conservation, and management efforts. Such efforts increasingly rely on human-made structures to achieve their respective goals. However, whether human-made structures support assemblages similar to those of natural habitat is equivocal in marine systems, and prior studies have often been based on short-term datasets (i.e., 2‑3 years). We used a ten-year dataset of fish surveys performed seasonally (i.e., quarterly) in conjunction with species’ trait data to identify patterns of community structure on reefs in the eastern Gulf of Mexico. The study sites were arranged in pairs of artificial and natural reefs, located near each other to control for the effects of abiotic (e.g., depth, temperature), biotic (e.g., larval supply, basal resources), and socio factors (e.g., access by fishers). We used species composition and abundance data to calculate community-weighted means for eight different functional traits that broadly describe the behavior and diet of the observed reef fishes. We then used multifactor mixed-effects permutational multivariate analysis of variance (PERMANOVA) coupled with canonical analysis of principal coordinates (CAP) to evaluate differences in taxonomic- and functional-diversity by reef type. CAP ordinations suggested artificial reefs were characterized by greater abundances of midwater or transient predators whereas benthic or demersal mesopredators were more abundant on natural reefs. This pattern was consistent across depth strata, although the explicit taxa contributing to differences varied with depth. These findings provide valuable insight regarding reef fish assemblage patterns in the eastern Gulf of Mexico and may provide essential information for assessing the efficacy of current and future management efforts for exploited species in this region.


Impacts of Tropical Herbivore Population Expansions on Seagrasses and Associated Fisheries in a Subtropical Lagoon

Presenter: Adam Searles *
Institution: University of Florida
Coauthors:
Doug Adams | Florida Fish and Wildlife Conservation Commission Fisheries Independent Monitoring Program
Lauren Hall | St. Johns River Water Management District
Lori Morris | St. Johns River Water Management District
Charles Martin | University of South Alabama
Laura Reynolds | University of Florida
Abstract:
Over the past 10 years, seagrass cover has declined 95% in the northern Indian River Lagoon (IRL), Florida. Concurrently, the abundance of the tropical herbivore, Western Atlantic sea bream (Archosargus rhomboidalis), has risen 49-fold. Growing sea bream populations and seagrass declines have the potential to exacerbate seagrass losses and increase competitive pressures for the local sheepshead (A. probatocephalus) fishery. Here, we employ 1) gut content analysis to quantify seagrass grazing and examine trophic overlap between these fishes and 2) long-term monitoring data to determine the influence of fine-scale seagrass cover on the dietary habits of these species. Preliminary results indicate that seagrass contributed to sea bream diet. Additionally, the diets of these species overlapped heavily and relied on commonly available macrophytes in the IRL. In the future, we aim to conduct feeding trials to understand the dietary preferences of these species.


Embrace the Bayesian in You: Examples from Somatic Growth

Presenter: Zachary Siders he/him/his
Institution: Fisheries and Aquatic Sciences
School of Forest
Fisheries
and Geomatic Sciences
University of Florida
Abstract:
Bayesian statistics are often not taught until the late stages of graduate school or until deemed exceptionally necessary. However, the Bayesian framework is seemingly more intuitive; use past information to help inform future expectations. Rarely in science do we repeat the same experiment ad nauseum or observe the same process under the exact same circumstances; conditions necessary to make full use of the more common Frequentist approach. Somatic growth is one case where the Bayesian approach excels. Exceptionally few growth studies collect specimens in the same manner at the same time and in the same location. For many species, sampling of some size classes can be challenging resulting in poor sample sizes across the species’ growth. For mark-recapture growth studies, individual growth can be highly variable which can make maximum likelihood approaches hard to fit. Also, we often make multiple measurements of age, like having several readers for otoliths, but throw out that data by averaging across reads to fit our models. Bayesian somatic growth models can help you with all of this and more. I will present examples of using Bayesian von Bertalanffy growth models to tackle common issues of sampling bias, viviparity, mark-recapture, and multiple readers from applications to sharks and rays, sea turtles, river cooters, and reef fish. Each example will build in complexity to showcase ways Bayesian approaches can be used to tackle multiple issues with estimating somatic growth. These methods range from the use of weakly informative priors, to bringing in extra data to inform size at birth or maximum size, to building hierarchical models to handle measurement error. In all, Bayesian approaches not only help your estimation but capitalize on the myriad of data we collect and the field observations we make.


Multidecadal Growth of Red Drum in Relation to the Deepwater Horizon Oil Spill and Other Driving Forces in the Gulf of Mexico

Presenter: Geoffrey Smith he/him
Institution: Northwest Florida State College/University of Florida
Coauthors:
Debra Murie | University of Florida
Amanda Croteau | University of West Florida/University of Florida
Daryl Parkyn | University of Florida
Abstract:
Sclerochronology was used to assess the impacts of the Deepwater Horizon oil spill on Red Drum growth. Multidecadal growth patterns were determined for male (n=99) and female (n=134) Red Drum ≥15 years of age collected between 2005 and 2016 from Louisiana (impacted area). Growth patterns were also determined for male (n=107) and female (n=94) Red Drum ≥15 years of age collected between 2005 and 2013 from west central Florida (control area). Growth increments of Red Drum from Louisiana were correlated to sea surface temperature (SST), the Mississippi River discharge, the Gulf of Mexico “Dead Zone”, the El Niño Southern Oscillation (ENSO), and the Atlantic Multidecadal Oscillation Index (AMO). We also used the occurrence and strength of previous tropical storms, hurricanes, and oil spills to estimate the extent of any growth changes due to a natural versus anthropogenic perturbation. Similarly, growth increments of Red Drum from Florida were correlated to SST, discharge of major rivers into Tampa Bay, ENSO, AMO, and tropical storms and hurricanes. For Red Drum from Louisiana, regardless of sex, spring SST appeared to be the only significant forcing factor among those analyzed. Tropical storms and hurricanes did not have an immediate impact on Red Drum growth but had minor delayed positive effects. Adding oil spills relative to hurricane events increased the correlation with the tropical storms/hurricanes and appeared to have similar positive delayed effects on Red Drum growth but still remained a non-significant forcing factor. Data from Florida Red Drum do not show the same correlation with spring SST, but do appear to show a significant negative correlation with river discharge. A similar pattern for negative correlation with river discharge was seen in Louisiana, but it was not significant. Overall, there is no evidence of impacts from the Deepwater Horizon or other oil spills in Louisiana waters to multidecadal growth patterns of Red Drum collected from Louisiana.


Peripheral Oyster Monitoring in Santa Rosa Sound

Presenter: Geoffrey Smith He/Him
Institution: Northwest Florida State College
Coauthors:
Isaac Todd | Northwest Florida State College
Abstract:
Oysters are vital components of estuarine systems found along the Atlantic and Gulf coasts of the US. They serve an important role as food, shelter, or both for numerous fish and invertebrate species, many of which have commercial or recreational importance. Oysters themselves are also harvested and provide several additional ecosystem services, including stabilizing shorelines against erosion from waves and filtering particulates out of the water. For these reasons, oyster populations are often monitored as a key component of estuarine health. In nearly all cases, monitoring of oyster populations focuses only on oyster reefs. In areas where there is a lack of proper settling habitat or where reefs have been impacted by various anthropogenic activities, there may appear to be few if any oysters. However, oysters often grow on other natural structures, such as shoreline vegetation, or anthropogenic structures such as dock pilings, seawalls, and rip rap shorelines. These peripheral oysters can make-up a substantial portion of local populations and perform many of the same ecosystem services (food, shelter, and filtration), and may serve as a source of larvae for establishing or restoring oyster reefs. Despite this, peripheral oysters are rarely monitored. This study utilized video footage of different potential peripheral oyster habitats in Santa Rosa Sound, FL to establish a baseline for their relative abundance and distribution. Sampling to date, suggests that there are substantial differences in oyster abundance based on substrate composition where concrete, metal, and rocky structures typically have greater oyster coverage than wooden structures and plastic structures often have few to no oysters.


Movement, distribution, and habitat preferences of Bullseye Snakehead in a quasi-natural system

Presenter: Courtney Stachowiak
Institution: Florida Fish and Wildlife Conservation Commission
Coauthors:
Max Inchausti | Florida Fish and Wildlife Conservation Commission
Dan Nelson | Florida Fish and Wildlife Conservation Commission
Nick Trippel | Florida Fish and Wildlife Conservation Commission
Abstract:
The Bullseye Snakehead (Channa marulius), a non-native freshwater fish species found in southeastern Florida canals, has been extensively monitored in south Florida since their introduction but little is known about potential impacts in natural open systems. To better understand the movement, distribution, and habitat preferences of Bullseye Snakehead in relation to other popular game fish species, Bullseye Snakehead, Butterfly Peacock Bass (Cichla ocellaris), and Largemouth Bass (Micropterus salmoides) were implanted with radio telemetry tags. In March 2021, a total of 25 of each of the three species, were collected from Lake Ida, surgically implanted with the tags, and released back into the lake. Active and passive tracking techniques were used from March 2021 to September 2022 to observe temporal changes in movement, distribution, and habitat preferences of each species in Lake Ida and the surrounding canals. Water temperature, dissolved oxygen, water depth, shoreline type, and species of aquatic vegetation present was recorded when individual fish were located during active tracking. One Bullseye Snakehead had traveled 15 miles north from the release location in the E-4 canal system during the study and was later caught by an angler even further north of its tracked location in Clear Lake. Preliminary results indicate Bullseye Snakehead generally prefer shallow areas of Lake Ida and the surrounding canals. Butterfly Peacock Bass and Largemouth Bass were more often found within the lake. The results of this study will be used to inform management of non-native and game fish species in south Florida.


A Population on the Brink: Striped Bass in the Ochlockonee River Drainage, Florida

Presenter: Stephen Stang
Institution: Florida Fish and Wildlife Conservation Commission
Coauthors:
Andy Strickland | Florida Fish and Wildlife Conservation Commission
Mike Allen | University of Florida
Abstract:
Lake Talquin and the tailrace located below the Jackson Bluff Dam provide a popular Striped Bass Morone saxatilis fishery in the Florida Panhandle. The system also serves as an important broodfish repository for hatchery programs participating in Gulf Striped Bass restoration efforts. In recent years, larger Striped Bass required for spawning purposes have become increasingly rare. This study sought to understand the underlying causes behind the reduction of larger size classes. Water temperatures and dissolved oxygen concentrations of creeks used as thermal refuge in Lake Talquin were measured during the summer of 2020. I found that marginal thermal and dissolved oxygen refuge exists for adult Striped Bass in Lake Talquin, and this refuge appears to be transitory in space and time. Threats from a changing climate are likely to degrade this critically important habitat. A total of 201 Striped Bass were tagged in Lake Talquin and below the Jackson Bluff Dam from December 2020 to February 2021. Annual exploitation was 25%, and there was evidence of substantial population connectivity between Lake Talquin and the lower Ochlockonee River via dam escapement. Exploitation was focused below the dam and limited to two cohorts of fish, and the harvest rate was greater for fish of larger sizes. An age sample was collected from December 2021 to January 2022 to examine population structure, and showed that Striped Bass appear to be growing rapidly until age-3 before experiencing high levels of mortality. Marginal summer habitat is likely contributing to very high levels of natural mortality and the truncated age structure of Striped Bass in Lake Talquin. Summer habitat is likely to degrade further in a changing climate, and changes in management strategies for this fishery are warranted.


Knowledge co-production: Integrating sport fish nursery habitat into land-use management

Presenter: Philip Stevens
Institution: Florida Fish and Wildlife Conservation Commission
Fish and Wildlife Research Institute
100 8th Ave SE
St Petersburg
FL 33701
Coauthors:
Courtney Saari | Florida Fish and Wildlife Conservation Commission, Fish and Wildlife Research Institute, 585 Prineville St, Port Charlotte, FL 33954
David Blewett | Florida Fish and Wildlife Conservation Commission, Fish and Wildlife Research Institute, 585 Prineville St, Port Charlotte, FL 33954
Matthew Bunting | Florida Fish and Wildlife Conservation Commission, Fish and Wildlife Research Institute, 585 Prineville St, Port Charlotte, FL 33954
Corey Anderson | Florida Fish and Wildlife Conservation Commission, Fish and Wildlife Research Institute, 585 Prineville St, Port Charlotte, FL 33954
Abstract:
In southwest Florida, coastal wetlands include tidal creeks and a series of semi-isolated coastal ponds at the upland interface. Ongoing research has found these habitats to be the primary nursery habitat for juvenile snook and tarpon. While snook and tarpon support major recreational fisheries in the region, nursery habitat availability may limit recruitment and population resilience. A collaboration has been developed to identify, monitor, conserve, and restore sport fish nursery habitat in a representative area of the Charlotte Harbor estuary experiencing urbanization. We are characterizing the physical attributes of restored and natural coastal ponds (e.g., depths, frequency of tidal inundation) and the dynamics of fish use (e.g., assemblages, densities, emigration of sport fish) to better inform land-use planners, stormwater engineers, and restoration practitioners. Preliminary findings show similar fish assemblages between natural and restored ponds, and link sport fish emigration to seasonal hydrologic connectivity. This collaborative effort has laid the foundation for a science co-production planning project for place-based recreational fisheries habitat conservation in Charlotte Harbor. Our findings are being directly incorporated into an applied research plan and used to adaptively manage restored fish habitat.


New innovative creel design combined with a high-reward tagging study to estimate Largemouth Bass abundance at Lake Okeechobee.

Presenter: Brandon Thompson
Institution: Florida Fish and Wildlife Conservation Commission
Coauthors:
Daniel Nelson | Florida Fish and Wildlife Conservation Commission
Matt Stevens | Florida Fish and Wildlife Conservation Commission
Abstract:
Lake Okeechobee is the largest lake in Florida at over 460,000 acres and one of the most economically important fisheries. The vast size and numerous access points at Lake Okeechobee limits the feasibility of conducting traditional creel surveys. Therefore, fisheries managers have run a partial lake roving creel survey for over 40 years that included several fixed sections of the lake that comprised less than 15% of the lake area. Surveyed areas historically included a relatively high portion of the total effort. However, as water levels and the quality of habitat change over time, resource biologists have been concerned that fixed areas sampled may not accurately represent trends in angler effort and catch. There was a need to design a creel that represented the entire lake and therefore, we developed an innovative creel design beginning in October of 2022 that utilizes a combination of trailer counts, angler interviews at primary boat ramps and on-the-water interviews. Managers were also interested in estimating Largemouth Bass abundance for the lake as the regulation schedule for the lake will be changing. Projected high water levels for extended periods during the year could have negative impacts on juvenile bass rearing habitat. Therefore, biologists initiated a high reward tagging study in January 2023. With estimates of total angler catch of bass from the new creel design in combination with estimates of the proportion of all bass caught from the tagging study, we can estimate the bass abundance prior to regulation schedule changes. Using this technique of annual whole-lake creels with periodic tagging (e.g., every five years) can help detect changes in the bass population over time. We will present preliminary results from the first year of these surveys and data will improve managers’ ability to make informed decisions at Lake Okeechobee.


Identification of host fish species parasitized by freshwater mussels of Florida

Presenter: Kallie Thornhill
Institution: Florida Fish & Wildlife- FWRI
Coauthors:
Lauren Patterson | Florida Fish & Wildlife- FWRI
Susan Geda | Florida Fish & Wildlife- FWRI
Abstract:
Nearly all freshwater mussels within the family Unionidae have a unique life cycle requiring a host fish to complete development from a larval mussel (glochidia) to a juvenile mussel. A vital component to understanding and managing mussel populations is knowledge of their host fish requirements and reproductive timing. In Florida, there are currently 61 described species, of which nine are federally endangered, seven are federally threatened, and 13 are designated by the state fisheries agency as species of greatest conservation need. Of the 61 species, host fish requirements are unknown for 26 species. We received Federal Section 6 funds to evaluate potential host fish for 10 species of freshwater mussel: one federally endangered species (Obovaria choctawensis, Choctaw Bean), one federally threatened species (Elliptio chipolaensis, Chipola Slabshell), and eight species petitioned for federal listing (E. ahenea, Southern Lance; E. arctata, Delicate Spike; E. fraterna, Brother Spike; E. monroensis, St. Johns Elephantear; E. purpurella, Inflated Spike; Strophitus radiatus, Rayed Creekshell; S. williamsi, Flatwoods Creekshell; Utterbackiana heardi, Apalachicola Floater). To achieve our goals, we spent the last three years renovating and expanding an aquaculture setup, collecting suitable host fish and mussel broodstock, inoculating the fish with viable glochidia, and subsequently monitoring to confirm any host fish species for our target mussels. This research has increased the life history knowledge of imperiled mussel species and will help make decisions on petitioned species listings and recovery plans.


Red Drum Hematological Health Relative to Pharmaceutical Exposure Across Florida Estuaries

Presenter: Shakira Trabelsi She/Her *
Institution: Florida International University
Coauthors:
Jennifer Rehage | Florida International University
Andy Distrubell | Florida International University
Nicholas Castillo | Florida International University
|
Abstract:
Pharmaceutically active compounds and their metabolites are a novel and emerging class of pollutants, recently being recognized as an increasingly concerning contaminant found in aquatic environments. Pharmaceuticals have been discovered at concentrations that have the potential to elicit profound effects in fish, and in Florida their presence and risk is unknown. The health of Red Drum (Sciaenops ocellatus) throughout Florida’s estuaries will be evaluated using hematological and blood biochemistry analyses and compared to pharmaceutical blood plasma levels to determine potential deleterious effects to health. Red drum were selected as an indicator species for pharmaceutical toxicity due to their continuous presence along the shores of Florida’s coast, benthic foraging in sediment, low mobility, and high site fidelity which makes them ideal for reflecting their local environmental conditions. Hematological analyses are an ideal parameter for investigating fish welfare, displaying changes to endocrine, reproductive, and immunological functions and can indicate chemical pollution, serving as a biomonitors conveying contaminant stress in the coastal marine environment.


A novel allopatric lineage within the fat snook species complex of the genus Centropomus

Presenter: Alexis Trotter
Institution: FL FWC / FWRI
Coauthors:
Seifu Seyoum | FL FWC / FWRI
Joel Anderson | TX Parks and Wildlife Department
Damon Williford | TX Parks and Wildlife Department
Michelle CD Hayes | FL FWC / FWRI (former)
Jynessa Dutka-Gianelli | University of Massachusetts
Miguel G Figuerola-Hernandez | University of Puerto Rico
Ronald G Taylor | FL FWC / FWRI (former)
Michael D Tringali | FL FWC / FWRI
Abstract:
Fat snook (Centropomus parallelus and Centropomus mexicanus) are widely distributed in coastal waters from Florida through Brazil, including parts of the Gulf of Mexico and many Caribbean Islands. The species-level taxonomy of these snook was explored with mitochondrial DNA 16S rRNA and cytochrome c oxidase subunit 1 sequencing and multilocus microsatellite DNA genotyping. The existence of a novel lineage first collected in Puerto Rico (Lineage 3) was confirmed in the presence of fat snook specimens obtained from Florida (presumptively C. parallelus, Lineage 1) and from Texas (C. mexicanus, Lineage 2). The novel lineage was found to be in the same phylogenetic clade as specimens from Brazil, consistent with distribution throughout the Caribbean and as far as South America. Lineages 1 and 2 are spatially isolated, with few fat snook reported along the GOM coast of FL and none reported from about Pensacola, FL through Freeport, TX. The transition zone between Lineages 2 and 3 may occur in the area between the Yucatán Peninsula and western Panama. Sampling from this region is necessary to identify the breakpoint and potential for hybridization. Analysis of sequence data within a maximum likelihood framework revealed that all three lineages form a monophyletic clade within Centropomus, with Lineage 3 ancestral to the currently recognized lineages, suggesting that Lineage 3 may have originated in South America and expanded to seed the other two. This expansion is estimated to have occurred 0.9−2.5 million years ago. Lineage 3 individuals occasionally migrate to the Atlantic coast of FL from the distal area of their distribution and hybridize with local specimens of Lineage 1, suggesting some overlap in the distribution of these two lineages. Overall, these data suggest a complex underlying phylogenetic history of fat snooks in the western Atlantic, with the potential for future taxonomic revision.


Risk of invasion for select ornamental tankbuster catfishes

Presenter: Quenton Tuckett he/him
Institution: University of Florida
Coauthors:
Timothy Lyons | New Mexico BioPark Society
Jeffrey Hill | University of Florida
Abstract:
Pet abandonment is an important introduction vector for freshwater aquarium fishes, which is potentially problematic Florida because it exhibits abundant access to freshwater habitats and a seemingly favorable climate. Studies have examined the factors affecting establishment for non-native species, including propagule pressure and climate suitability. Maximum body size can increase pet abandonment and ultimately propagule pressure as pets become too large for tank dimensions and are released. Several of these “tankbuster” catfishes are found in the aquarium trade, including the Goonch Bagarius spp., Redtail Catfish Phractocephalus hemioliopterus, and several species of Sorubim Catfish, Barred Sorubim Catfish Pseudoplatystoma fasciatum, Spotted Sorubim Catfish P. corruscans, and Tiger Sorubim Catfish P. tigrinum. To examine the risk of invasion, all five species were screened using the Fish Invasiveness Screening Kit (FISK). We also determined the chronic lethal minimum temperature for three of the readily available catfishes. All five species returned scores that placed them into the medium risk category. Redtail Catfish scored lowest with a 3 and Spotted Sorubim Catfish the highest with a 9. Certainty was high, ranging from 0.76 for Redtail Catfish, Spotted Sorubim Catfish, and Barred Sorubim Catfish to 0.83 for Tiger Sorubim Catfish. Tolerance estimates for the three species were higher than many other ornamental species, highest for the Redtail Catfish (14.3°C), lower for the Tiger Sorubim Catfish (11.0°C), and lowest (9.9°C) for the Goonch. Given these lethal temperatures, the distribution of Redtail Catfish would be limited South Florida while the Tiger Sorubim Catfish and Goonch could survive to ~28° N Latitude in Florida, but would be mitigated by riverine spawning requirements. We identify and discuss three risk management options: 1) maintain the status quo, 2) additional risk assessment for the highest scoring species, Spotted Sorubim Catfish, and 3) move some or all these species to the conditional species list.


Fish removal at Lake Wauberg to evaluate changes in growth of Black Crappie

Presenter: Travis Tuten
Institution: Florida Fish and Wildlife Conservation Commission
Coauthors:
Nicholas Ducharme-Barth | NOAA
Chris Anderson | Florida Fish and Wildlife Conservation Commission
Jason O’Connor | Florida Fish and Wildlife Conservation Commission
Eric Nagid | Florida Fish and Wildlife Conservation Commission
Paul Schueller | Florida Fish and Wildlife Conservation Commission
Mike Allen | UF
Abstract:
Lake Wauberg is a 100-ha hypereutrophic lake in North Central Florida. There have been multiple fish research projects on the lake in the past 25 years and the Black Crappie Pomoxis nigromaculatus population has been monitored annually with trawl samples since 1998. It was known to have a highly dense fish community, with the Black Crappie population exhibiting slow growth with many individuals in upper age-classes stunted below 230 mm TL. Our objective was to evaluate changes in growth of the Black Crappie population in response to a fish density and biomass reduction. We used trawls to capture and remove fish from the lake, and evaluate changes in catch rates and size structures from our removal efforts. From 2014 to 2016, we pulled a total of 654 trawls and removed 60,788 fish weighing 6,897 kg from the lake during three removal events. Black Crappie made up the largest portion of fish removed during the three years of the removal efforts, consisting of 29,290 (48.2%) of the total fish by number and 1,960 kg (28.4%) of the total weight. Brown Bullhead Ameiurus nebulosus made up the second most fish removed with 15,944 (26.2%) of the total number and 3,605 kg (52.3%) of the total weight. Our removal efforts were successful at lowering the abundance of Black Crappie and Brown Bullhead based on large declines in CPUE. We continued to annually monitor the Black Crappie population after the removal efforts and evaluate changes in growth in response to changes in abundance.


A behavioral comparison and a review of impacts on two worldwide freshwater fish invaders- Gambusia holbrooki and G. affinis

Presenter: Elizabeth Walsh She/Her *
Institution: University of Florida
Coauthors:
Quenton Tuckett | University of Florida
Jeff Hill | University of Florida
Abstract:
The Eastern Mosquitofish (Gambusia holbrooki) and the Western Mosquitofish (G. affinis) are two closely related species introduced around the world for the control of mosquitos since the early 1900s. These two species are known for displaying highly aggressive behavior towards small-bodied fish and tadpoles and have even earned the nickname “Plague Minnow”. Currently, both species have one of the largest ranges and longest record of ecological impact of any introduced fish. Despite their morphological similarity, recent studies suggest differences in aggression and invasiveness between the two species in the presence of a third global invader, the Guppy (Poecilia reticulata) — with extirpation of Western Mosquitofish in Japan and extirpation of Guppies in Florida. The goal of my research was to determine if the two Mosquitofish species differ in behavior and invasiveness through (I) aquarium trials in which compared aggression, boldness, and sociability (II) mesocosm experiments that compared impacts on a population of Guppies and (III) a review of the scientific literature that compared documented impacts between the two species. Eastern Mosquitofish were more aggressive compared to Western Mosquitofish and caused more severe impacts. Western Mosquitofish were bolder, and tendency to shoal was similar between species. The scientific literature indicated many similarities in behavior and impacts, but highlighted complications of species identity as over 89% of studies on Eastern Mosquitofish confirmed species identity, whereas only 9% of studies on Western Mosquitofish confirmed the identity. These results emphasize the importance of correct species identification as their behavior and invasiveness differ, despite their extreme similarities in morphology and life history.


Juvenile Gulf Sturgeon (Acipenser oxyrhynchus desotoi) movements in the Pensacola Bay Watershed

Presenter: Bradford Warland
Institution: Florida Fish and Wildlife Conservation Commission
Coauthors:
Kirsten Humphries | Florida Fish and Wildlife Conservation Commission
Abstract:
Gulf Sturgeon (Acipenser oxyrinchus desotoi) are theorized to have differing habitat use patterns at different life-stages. To better understand these differences juvenile and subadult individuals were acoustically tagged in the Yellow and Escambia rivers during the sampling periods. They were monitored by a Pensacola bay watershed acoustic array (N=74) year round to determine differences in habitat use between the cohorts. Fine(5km) scale movements were observed among all individuals in the rivers and bays with the juveniles(age 1-4) showing a higher fidelity to the river mouths during the winter movements in the estuarine and marine environments. Understanding the drivers of these movements and preferred habitats will better inform conservation efforts that may be focused on the winter use areas of juveniles, which is likely where the highest mortality occurs in this species life cycle.


Do changes in natural habitat availability affect sportfish?

Presenter: Sarah Webb *
Institution: FAU-HBOI
Coauthors:
Erick Ault | Florida Fish and Wildlife Conservation Commission
Robert Ellis | Florida Fish and Wildlife Conservation Commission
Matthew Ajemian | FAU-HBOI
Philip Stevens | Florida Fish and Wildlife Conservation Commission
Abstract:
The St. Lucie Estuary is a diverse and productive portion of the larger Indian River Lagoon in southeast Florida. Development and urbanization have affected the natural habitats that included mangroves, oyster reefs, and seagrass beds throughout this estuary. Locally sourced runoff and excessive freshwater discharges into the estuary can stress the system. Various fish species rely on these habitats for some or all their life stages, including goliath grouper (Epinephelus itajara), sheepshead (Archosargus probatocephauls), and spotted seatrout (Cynoscion nebulosus). Some researchers have suggested that the St. Lucie Estuary is not an ideal nursey habitat for fish. However, observations of these species still occur. This study aims to identify how large-bodied fish have responded to a heavily urbanized estuary. Here, we use data from long term fisheries monitoring, seagrass and habitat mapping, and acoustic telemetry to identify how fish species may shift habitat use patterns in response to changes in habitat availability . The goal of this work is to document the changes that have occurred over time and to determine how, and if, the St. Lucie Estuary and southern Indian River Lagoon function as suitable habitat for valuable sportfish.


Reproductive Potential of Gray Snapper in Spawning Aggregations off the West Coast of Florida

Presenter: Ashley Wechsler *
Institution: University of Florida
Coauthors:
Debra Murie | University of Florida
Abstract:
Gray Snapper Lutjanus griseus is a member of the lutjanid family and resides in the Gulf of Mexico and the Western Atlantic from North Carolina to Brazil. They are also known locally as Mangrove Snapper and are highly valued as a recreational species with the greatest harvest along Florida’s west coast. The Gulf of Mexico stock has been undergoing overfishing since the mid 1970’s, however the most recent stock assessment in 2022 recognized it as no longer undergoing overfishing. Gray Snapper may be particularly vulnerable to fishing pressures as they form spawning aggregations during the summer months concurrent with the lunar cycle. Fish were collected offshore, primarily in the vicinity of the Middle Grounds, between April and December 2022. Females (n=920) ranged in size from 280 mm to 678 mm total length (TL) and males (n=1433) were 276 mm to 697 mm TL. In a preliminary analysis, macroscopic and limited histological examination of ovaries indicated that females are asynchronous, indeterminate batch spawners. This means that individual fish spawn at different times within the spawning season (females contain oocytes in various developing stages at the same time), continuously recruit new oocytes during the spawning season, and develop and release multiple batches of mature oocytes over an annual spawning season. Females were found to be spawning capable between June and September, and actively-spawning (i.e., visibly hydrated eggs as seen macroscopically) from July to early September. Ovarian weight as a proportion of female weight (GSI) also peaked in June to August. In contrast, gonadal and visceral fat of females decreased during July through September and was presumably used by females as a source of energy during the spawning period. Future analysis will determine age and size of sexual maturity, as well as spawning season duration, spawning frequency, and batch fecundity.


Movement and Habitat Use of Alligator Gar in Pensacola Bay

Presenter: Matt Wegener
Institution: Florida Fish and Wildlife Conservation Commission
Coauthors:
Amanda Mattair | Florida Fish and Wildlife Conservation Commission
Calvin Beech | Florida Fish and Wildlife Conservation Commission
Mark Barrett | Florida Fish and Wildlife Conservation Commission
Brandon Barthel | Florida Fish and Wildlife Conservation Commission
Abstract:
Conservation and management of Alligator Gar is an emerging topic, as the role of this apex predator continues to be better understood. In Florida, the conservation status is currently being re-evaluated, so an understanding of critical habitats is paramount for an accurate designation. Normally considered a riverine species, movement results during initial research indicated a remarkable ability for individuals to traverse saline waters. Additional telemetry results from a subsequent study indicated even more use of bay habitats and infrequent visits into riverine habitats where they were initially captured. These observations led researchers to broaden their telemetry project to include all of Pensacola Bay and its tributaries. Results suggest bay habitats are predominantly used from fall until early spring. Fish move into river habitats, primarily the Escambia River, in the spring and stay there through early summer. These movements generally coincide with rising river levels. It is unclear why this seasonal shift in habitat occurs, but the timing suggest it may be related to spawning. By midsummer, tagged Alligator Gar move from river to bay habitats, before settling in bay habitats for the winter. Coastal river and bay habitats are complex and understanding how Alligator Gar utilize individual components throughout their life cycle is critical to the future conservation and management of this species. Alligator Gar in Pensacola Bay utilize river and bay habitats at different times during the year and the Escambia River appears to be of particular interest during their spring migration.


When world’s collide: consumer nutrient dynamics in the Florida Coastal Everglades

Presenter: Mack White he *
Institution: Florida International University
Coauthors:
Jennifer Rehage | Florida International University
Rolando Santos | Florida International University
Ryan James | Florida International University
Ryan Rezek | Coastal Carolina University
Jordan Massie | Florida International University
Natasha Viadero | Bonefish & Tarpon Trust
Abstract:
The transport of resources by migratory animals is an important, yet under-appreciated component of resource budgets in many ecosystems. In particular, nutrient contributions from migratory fishes can have profound effects on recipient ecosystem function and structure. In the Shark River, ENP fishes migrate into perennial mangrove creeks during the annual dry season to either seek refuge from falling water levels in adjacent marsh habitats or track the resulting prey subsidy, moving from downstream estuarine environments. Evidence from stable isotopes indicate that Common Snook can link food webs across large spatial extents in the Shark River. However, the full extent of consumer nutrient dynamics (CND) for both estuarine and freshwater fish communities have yet to be explored. Here, I discuss my ongoing research to quantify the magnitude and inter-annual variability of CND in the marsh-mangrove ecotone using a combination of bioenergetics modeling and acoustic telemetry. Given realized and projected changes to hydroclimatic conditions as a result of climate change and ongoing restoration efforts, a better understanding of the magnitude and drivers of CND will provide a more holistic understanding of how nutrients cycle throughout the Everglades landscape with implications for ecosystem-level management.


Niche partitioning between endemic and range-expanding fishes in search of winter refuge

Presenter: Kyle Williams
Institution: FL Fish and Wildlife Conservation Commission
Fish and Wildlife Research Institute
Coauthors:
Alexis Trotter | FL Fish and Wildlife Conservation Commission, Fish and Wildlife Research Institute
Philip Stevens | FL Fish and Wildlife Conservation Commission, Fish and Wildlife Research Institute
Micheal Allen | University of Florida, Institute of Food and Agricultural Sciences, Nature Coast Biological Station
Abstract:
Common Snook Centropomus undecimalis (hereafter snook) has been expanding northward in Florida in response to warmer winters. In areas north of Tampa Bay, estuarine water temperatures still approach the species’ lower lethal limit (ca. 9 °C) and snook are using spring-fed rivers as warmwater refuge during winter. Anglers and local communities have become accustomed to and now target snook, although there are concerns about how this range expansion affects other sportfish endemic to the region such as Red Drum Sciaenops ocellatus (hereafter red drum). A two-pronged research project is being conducted to evaluate habitat and diet overlap of these species in Crystal River, the largest spring system in the area. Acoustic telemetry will examine the movement patterns of snook and red drum to determine 1) if there is any spatial overlap and 2) how their distributions change during the passage of cold fronts. Gastric lavage will be used to compare diets and estimate trophic overlap between snook, red drum, and Florida Largemouth Bass Micropterus salmoides floridanus (hereafter bass). So far, snook tagged in 2021 (n=39) tended to move to the river’s headwaters where a concentration of springs occurs when water temperatures near the coast fell below 22 °C. Fisherman have suggested that red drum will also move into deep holes within the river and creeks at the same time, potentially increasing competition for space and food. While these species do not appear to directly compete for resources in other areas where they co-occur, the relatively small spatial area and limited prey availability may increase these interactions. Further, the timing of when they occur together is also the time when young-of-the-year of all three species could be using the river as nurseries and could become prey. This presentation will concentrate on preliminary movement data and field observations.


Reeling in Anglers: Recruitment and Retention for Fisheries-Based Citizen Science

Presenter: Meg Withers She/Her/Hers
Institution: South Atlantic Fishery Management Council
Coauthors:
Julia Byrd | South Atlantic Fishery Management Council
Abstract:
The South Atlantic Fishery Management Council (SAFMC) manages fish stocks in U.S. federal waters from North Carolina to the Florida Keys. Gathering data on fish that are caught and released is critical to fisheries management. However, this information is difficult to collect through traditional sampling methods. Thus, SAFMC is partnering with anglers to collect data on their released fish through the citizen science project SAFMC Release. Using the mobile app SciFish, anglers are recording information, such as fish length, depth caught, and hook type, before releasing their fish.

Our initial efforts focused on the recruitment of participants. This was done through social media, newsletters, mailings, in-person tackle shop visits, and seminars, among other outreach methods. About 33% of our participants learned about the project through a mailing sent to anglers in North Carolina in collaboration with the North Carolina Department of Natural Resources. Another 28% heard about the project through personal contact with staff. These results illustrate the importance of relationships and partnerships to an effective citizen science project. Establishing these relationships has both supported SAFMC Release’s growth and further opened the fisheries science and management process to anglers.

Our efforts are shifting from recruitment to retention, as a key challenge for the project has been inconsistent submission of data. We aim to address this by fostering meaningful connections with participants, building a sense of community, offering goals to be met, and collaborating with partners who can offer incentives.

Through our presentation, meeting attendees will learn about the challenges of fisheries science and management, how SAFMC Release helps to address these challenges, and the effectiveness of our outreach thus far. In turn, we hope to receive feedback from attendees regarding our retention strategies and to identify new or improved methods for achieving our retention goals.


Teasing apart the source and composition of reef fish discards in the Gulf of Mexico

Presenter: Selia Zimmermann *
Institution: Fisheries and Aquatic Sciences
School of Forest
Fisheries
and Geomatic Sciences
University of Florida
Coauthors:
Nancy Montes | Florida Sea Grant, University of Florida
Charles Sidman | Florida Sea Grant, University of Florida
Zachary Siders | Fisheries and Aquatic Sciences, School of Forest, Fisheries, and Geomatic Sciences, University of Florida
Abstract:
Discard mortality resulting from barotrauma is a leading concern for the sustainable management of Gulf of Mexico reef fisheries. Reef fish are discarded for a variety of reasons but principally as a result of interacting length limits, bag limits, and season limits. The DESCEND Act (Public Law 116-340) requires venting and descending devices to be onboard and ready for use for all fishing sectors in the Gulf of Mexico Exclusive Economic Zone. To encourage anglers to use these devices, the Return Em’ Right program was created to educate anglers on best practices for discarding reef fish and disseminate venting and descending devices to anglers participating in the program, currently 12,398 anglers throughout the Gulf of Mexico. In early 2023, we surveyed 7,000 of the participating anglers with 1,198 total responses. From ~900 responses, most anglers had completed their last reef fishing trip in the prior two months and fished mostly for Red Snapper (31%) and Gag Grouper (18%). From these trips, anglers released predominantly Red Snapper (28%), Red Grouper (18%), Gag Grouper (17%), and Gray Triggerfish (12%). Red Snapper and Gray Triggerfish were released primarily for being out of season while Red Grouper and Gag Grouper were released for being too small. Only 20% of anglers indicated that saw no signs of fish with barotrauma on their last fishing trip with most anglers using descending devices or dehooking tools to release fish. Our survey likely targets the most avid of Gulf of Mexico reef fish anglers but provides valuable linkages between target species and discard species as well as enumerates why anglers released fish. This represents valuable information that is not available in the larger, more representative Marine Recreational Information Program surveys, which enumerates the target species and only the number of discards.