Florida Fish Research Articles

The economic benefit of spearfishing as an impure public good: A case study of invasive Lionfish in Florida

Lionfish (Pterois miles and P. volitans) is a highly invasive species originally from the South Pacific and Indian Oceans. As an effort to control its exponentially growing population, the Florida Fish and Wildlife Conservation Commission has launched a program called “Lionfish Challenge” to promote harvesting of lionfish from Florida waters. The program provides anglers with a unique recreational opportunity because they would need to dive and spearfish to harvest lionfish. Furthermore, participants in the program not only gain utility from spearfishing as a private good but also as a public good, knowing that they are contributing to the ecosystem in Florida waters. This paper contributes to the literature by measuring the economic benefit for participants from spearfishing as an impure public good. Using data provided by the Florida Fish and Wildlife Conservation Commission, a travel cost method was applied to model the demand for lionfish fishing trips. Data included information about counties where lionfish were harvested at the trip-level, but only if participants took a trip and harvested lionfish. Therefore, those who are good at catching lionfish had a higher probability of being included in the data. To account for potential sample selection bias, a probability weight was applied, using the average number of lionfish harvested as a proxy. Results indicate that the per-trip consumer surplus per participant was between $965.89 and $1,597.36, depending on model specifications, with the preferred specification indicating a mean CS of $1,117.72 per trip. The seasonal consumer surplus per participant was indicated to be between $4,550.45 and $3487.91, again, depending on model specification.

Recreational angler preferences for, and potential effort responses to, different red snapper management approaches

AbstractThe Gulf of Mexico red snapper fishery has been caught in a spiral of more restrictive regulations and disputed management. Current management measures have failed to reduce fishing mortality, owing in part to derby style fishing. A harvest tag system could potentially better limit fishing mortality without decreasing harvest seasons. In 2019/20 we surveyed 766 recreational anglers who fish in Florida with private boats to ascertain their preferences for regulation changes, 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 most 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. Harvest tags, though not preferred by all respondents, may allow regulators to better manage the number of anglers in the fishery and to rebuild the stock, although implementing this program will pose some challenges.

Estimates of Western Atlantic Goliath Grouper (Epinephelus Itajara) Bycatch Mortality in Commercial Fisheries of the Southeastern United States From 2002 to 2022

The Atlantic Goliath Grouper (_Epinephelus itajara_) in the southeastern United States is in decline due to increasingly large and persistent red tides, loss of juvenile habitat, and severe cold-weather events. In this paper, we address another source of mortality -- bycatch, focusing on data from NOAA Fisheries logbooks for commercial fisheries operating between 2002 to 2022. We calculate capture related mortality based on known patterns of depth-related barotrauma drawn from the literature and assume that all fish captured at depths greater than 30 m died if unvented prior to release. The overall result suggests that 75% (14,124 of 18,770) of Goliath Grouper captures died from barotrauma, as they either hemorrhaged or were unable to return to the bottom because of increased buoyancy due to expanded gas trapped in the swim bladder. While fishers currently use self-reporting to document these mortalities, this approach often results in biases toward lower capture and a higher survival rate. Thus, we strongly urge the Florida Fish and Wildlife Conservation Commission and the National Oceanic and Atmospheric Administration to quit using logbook data and instead require that fishers use paid observers and remote electronic monitoring on all commercial and charter vessels to ensure more effective, timely and reliable bycatch data for this and other protected species.

Fusing remote sensing data with spatiotemporal in situ samples for red tide (Karenia brevis) detection.

We present a novel method for detecting red tide (Karenia brevis) blooms off the west coast of Florida, driven by a neural network classifier that combines remote sensing data with spatiotemporally distributed in situ sample data. The network detects blooms over a 1-km grid, using seven ocean color features from the MODIS-Aqua satellite platform (2002-2021) and in situ sample data collected by the Florida Fish and Wildlife Conservation Commission and its partners. Model performance was demonstrably enhanced by two key innovations: depth normalization of satellite features and encoding of an in situ feature. The satellite features were normalized to adjust for depth-dependent bottom reflection effects in shallow coastal waters. The in situ data were used to engineer a feature that contextualizes recent nearby ground truth of K. brevis concentrations through a K-nearest neighbor spatiotemporal proximity weighting scheme. A rigorous experimental comparison revealed that our model outperforms existing remote detection methods presented in the literature and applied in practice. This classifier has strong potential to be operationalized to support more efficient monitoring and mitigation of future blooms, more accurate communication about their spatial extent and distribution, and a deeper scientific understanding of bloom dynamics, transport, drivers, and impacts in the region. This approach also has the potential to be adapted for the detection of other algal blooms in coastal waters. Integr Environ Assess Manag 2024;20:1432-1446. © 2024 SETAC.

Controversial opening of a limited fishery for Atlantic Goliath Grouper in the United States: Implications for population recovery

Laws protecting the Atlantic Goliath Grouper Epinephelus itajara from fishing in federal and state waters of the United States (US) occurred in 1990 after the species was identified as being severely overfished. Population increases that occurred during the first 20 years of the closure were followed by a decline in the 10 years thereafter. Despite the National Oceanic and Atmospheric Administration’s call to retain full protection for this species in federal waters, the Florida Fish and Wildlife Conservation Commission (FWC) decided to open a limited fishery in state waters for juveniles. Here, we review the literature demonstrating the initial recovery of Goliath Grouper in the U.S., the limits of that recovery, and the ensuing factors that precipitated its subsequent decline; we discuss the risks associated with management decisions that ignore the best available scientific information; and we compare management differences and difficulties among nations within the Atlantic Goliath Grouper’s global range. The major findings are that Goliath Grouper populations have not fully recovered and that FWC has not sought to conserve and protect them. Resolving these problems will require the Governor of the State of Florida to appoint Commissioners that represent a range of stakeholders with expertise in ecology, conservation, and management beyond that provided by the FWC agency; to better train appointees lacking in those areas; and to choose candidates who embrace use of the best available science in making critical decisions that affect Florida ecosystems, native species, and Florida residents.

Dorsal Fin Spines and Rays for Nonlethal Ageing of Goliath Grouper Epinephelus itajara

Atlantic Goliath Grouper, Epinephelus itajara, the largest grouper in the western North Atlantic, exhibits life history characteristics (e.g., it is slow-growing, long-lived, and late-maturing) that make it particularly susceptible to fishing pressure. Otoliths, the structure typically processed for age determination, are usually collected as part of fishery monitoring, but otoliths are not available from Goliath Grouper due to a harvest moratorium enacted in 1990 for United States waters. Alternative structures—such as dorsal fin rays or spines—can be acquired for ageing via nonlethal sampling and may provide reliable age estimates. Since 2006, the Florida Fish and Wildlife Conservation Commission (FWC) has been collecting incidental Goliath Grouper samples from mortality events including those from cold kills and red tides. Corresponding otolith, dorsal fin ray and dorsal fin spine samples were compared to determine the accuracy and precision of the external ageing structures. Marginal increment analyses indicated that annulus (translucent zone) deposition occurred primarily in March–June on spines and in April–June on rays. While ages determined from both rays and spines exhibited high precision, the accuracy compared to otolith ages was low as a result of systematic underageing of both external structures, particularly at the oldest age classes. A correction factor was applied to rays and spines that remedied the underageing, but the correction factor was more successful for spines. An analysis of ray and spine section accuracy based on nonlethal structure removal from the fish (i.e., comparing ages from sections at the base of the structure within the body to those sectioned from the external surface of the body) determined that spines can be accurately aged when sampled distal of the base of the structure, but that rays cannot. Nonlethal sampling and ageing of Goliath Grouper spines facilitated by public participation could address management goals and help determine the offshore population age structure. Simultaneously, it could contribute critical data needed for a traditional stock assessment, should such a path be warranted by the recovery or management of the species.

HABs Karenia brevis and Pseudo-nitzschia pre- and post-Hurricane Michael.

Increased occurrences of harmful algal blooms (HAB) in the Gulf of Mexico, and even worldwide, yield concern for increases in brevetoxin exposure leading to respiratory illness or even death, highlighting the need for extensive scientific research and human health monitoring. It is known that major events such as tropical storms and hurricanes are followed by periods of increased red tides caused by HABs; however, the nature by which phytoplankton blooms proliferate following major events remains a topic of great interest and research. The impact of Hurricane Michael on October 10, 2018 on HABs in the Florida panhandle was examined by analyzing data from the Florida Fish and Wildlife Conservation Commission in coordination with Normalized Fluorescence Line Height (nFLH) data from the University of South Florida College of Marine Science. Results presented here demonstrate four phases of HABs during storm events: 1. Pre-storm concentrations, 2. Decreased concentration during the storm, 3. Elevated concentrations following the storm and 4. Recovery period. This time frame can serve to be important in understanding the health dynamics of coastal systems following major storm events.

Mapping Past Distributions of Marine Mollusks Using Shell Death Assemblages

Marine species assessments rely heavily on baseline surveys conducted after the 1960s, long after many anthropogenic pressures began, which could lead to misinformed management decisions and poor conservation outcomes. In this study, we collaborated with Florida Fish and Wildlife to conduct stock assessments for mollusks of the west Florida shelf that incorporate shell death assemblages. One of our first assessments was of the Florida Fighting Conch, Strombus alatus, an abundant gastropod that is also under consideration as a replacement fishery for the threatened Queen Conch. Live and dead shells were collected from >300 dredge tows between 2008-2018 covering the entire west Florida shelf. Shells were age-partitioned by 14C- and AAR-calibrated taphonomic criteria. Counts were converted to densities per m2. Inverse distance weighting interpolation of S. alatus death assemblages reveals multiple population centers along the coast and a rapid decrease in density with depth from 25-120 m. In contrast, live conchs were absent in our dredge samples from shelf depths deeper than 40 m. These differences are confirmed by single-visit occupancy methods that account for variation in detectability across the samples. Live-dead differences in spatial distribution are probably influenced by time averaging in death assemblages, which increases detectability of conchs in deeper habitats, where they may be too rare to be sampled alive. However, extirpation of offshore populations was also indicated by independent natural history collection occurrence records, which show numerous live-collected conchs from 1940-1980 but none afterwards, despite an increase in sampling effort. These results suggest that live-dead comparisons can reveal biodiversity loss at the scale of large marine ecosystems.

Death Assemblages Record Significant Range Contraction in a Molluscan Species of Concern from the Eastern Gulf Of Mexico

Marine habitats are in decline due to increasing anthropogenic pressures, but baseline data on species distributions needed to manage and conserve populations are lacking. Incorporating death assemblages into species assessments can create a more accurate understanding of pre-anthropogenic communities than survey records alone. In this study, we conducted a live-dead analysis on mollusks from a new 2008-2018 dredge survey in the eastern Gulf of Mexico. We selected the predatory banded tulip snail, Cinctura hunteria, as a test case for assessment because this species is one of several designated by the Florida Fish and Wildlife as a species of concern. Using spatial count data for shells in our samples, we estimated density values for each taxonomic grade over the sampled area using IDW spatial interpolation. These maps reveal large areas of occupation across the west Florida shelf for two taxonomic grades of dead shells but loss of offshore occurrence for live records. One explanation for the lack of occurrences in offshore habitats is that, unlike dead shell records, there is no time averaging accumulation of live shells. Time averaging increases detectability of species in habitats where they are rare. However, independent fisheries data from live-only animal surveys not only mirror our live-dead results but suggest that habitat loss in our live-dead comparisons was rapid and occurred in the late 1980s or early 1990s. Thus, live-dead comparisons reveal both natural baselines as well as anthropogenic changes in distribution without being significantly distorted by time-averaging biases. Including live-dead data can greatly improve species assessments when long-term survey records are unavailable and provide a key tool in combatting biodiversity loss across marine ecosystems.

Comparative assessment of the U.S. State of Florida’s Marine Life regulations for its commercial marine aquarium fish fishery

Governments in select locales around the world have recently either restricted or closed commercial marine aquarium fisheries, impacting the livelihoods of fishers, traders, and others who depend on them. This paper offers an objective assessment of Florida's commercial marine aquarium fish fishery and its regulatory landscape to inform and guide stakeholders about management strategies for the fishery moving forward, and to highlight successful regulations in place in Florida that merit consideration for adoption in other source locales around the world. The study discovered that the State has a strong regulatory structure for the commercial fishery operated by the Florida Fish and Wildlife Conservation Commission; practicing co-management with fishers, and utilizing license and permitting requirements, conventional fisheries management measures and technical actions to regulate fishing mortality, and rights-based management approaches. Additionally, both fisheries-independent and dependent surveys have been conducted in recent years to assess the fishery. Consequently, the vast majority of fish species collected commercially for the trade indicate stable or increasing catch trends in Florida waters over 10 + years. Moving forward, the fishery can benefit from an assessment of the economic impacts of the regulatory framework on its fishers, a statewide fisheries management plan specific for the fishery, the further development of a comprehensive program for fisheries data collection and analysis to address data gaps, an assessment of resources at hand and those needed to implement these recommendations, and the elevation of marine aquarium fisheries for support at the national level to support state-level management.

Exploring the hidden connections between information channel use and pro-environmental behavior among recreational anglers of the shore-based shark fishery in Florida, United States

IntroductionShore-based shark fishing in Florida is a relatively low-cost and easy-access fishery which attracts a wide variety of experienced and inexperienced anglers leading to concerns about proper handling methods of captured fish that are released either voluntarily or to comply with regulations. Proper handling methods can help reduce post-release mortality among sharks, many of which are threatened with extinction. Therefore, we considered proper handling methods as a pro-environmental behavior, which has been linked with the use of different information channels to increase conservation knowledge.MethodsWe used data from an online questionnaire to understand where anglers of this fishery obtain information about fishing skills with a particular focus on fish handling techniques and best practices for catch-and-release. Then we included their main information channels in a series of hierarchical regression models with perceived conservation knowledge and support for fishery management to explain pro-environmental behavior regarding shark conservation.ResultsWe found that most anglers learned about shore-based shark fishing through interpersonal communications with friends and family, but typically use the internet to learn more about fishing skills. While information channel use was not significantly associated with pro-environmental behavior, it was significantly associated with support for fisheries management, which in turn was associated with pro-environmental behavior among respondents.DiscussionThese findings can inform public educational outreach efforts to spread awareness of proper handling techniques and reduce instances of post-release mortality in sharks.

How Oyster Reefs Can Affect Finfish Recruitment

Recruitment is a very important life stage for fish which has direct impacts on size of the whole fish population. During this phase, the mortality juvenile fish experience is affected by their density because of competition for the available resources. How much fish density affects mortality in recruitment is itself affected by many factors, but one of the most important is the structural habitat available to juvenile fish. Structurally complex habitats like oyster reefs are thought to have a particularly strong influence on the recruitment process of certain species. Here we describe the ways that habitat can alter recruitment success. We focus on how oyster reefs affect recruitment of fish in Florida and the particular issues related to management of this important habitat.

Fish community assessment of shelf-edge artificial reefs along east-central Florida

Artificial reef development is a popular management tool used to enhance fish stocks, mitigate degradation or loss of natural habitats, and provide additional recreational opportunities. In Florida, artificial reef development is a top priority of the Florida Fish and Wildlife Division of Marine Fisheries Management’s Artificial Reef program; however, despite their popularity and support, our scientific understanding of how artificial reefs ecologically facilitate marine fisheries is limited in certain habitats. This is especially true of the many artificial reefs along Florida’s central east coast, which has received sporadic assessment over the past few decades. The objective of this study was to conduct a fishery-independent assessment of the reef fish communities inhabiting the artificial reef sites off central east coast Florida using a combination of vertical longline sampling (VLL) and baited remote underwater videos (BRUV). Red snapper (Lutjanus campechanus) and vermilion snapper (Rhomboplites aurorubens) had the largest catch-per-unit-effort (CPUE) during VLL sampling, with red snapper CPUE significantly greater on rubble artificial reefs deeper than 40 m and vermilion snapper CPUE significantly greater on artificial reefs shallower than 30 m. A total of 62 fish species were observed on BRUVs, and community analysis indicated that red snapper, vermilion snapper, and tomtate (Haemulon aurolineatum) contributed the most to differences in community composition. Red snapper had the greatest abundance on sites deeper than 40 m, while vermilion snapper and tomtates had greater abundance on sites shallower than 30 m; all three species were more abundant during summer. This study provides the first quantitative assessment of reef fish communities on artificial reefs along central east coast Florida. Further monitoring is encouraged to unravel possible interactive effects of reef type and other environmental factors on fish assemblages, although it is evident that the reefs sampled support multiple managed fisheries species.

‘A human values issue’: Actors, arguments, and regulatory change in the Florida land‐based shark fishery

Abstract Recreational shark fisheries have been the subject of recent public attention because of the possible impacts on shark populations and conflicts between stakeholders. A case study is presented based on discussions that took place in summer 2018 about potential changes to policies regulating recreational land‐based shark fishing in Florida. Comments from public meetings and workshops (totalling 15.8 hours) and online comments (1,050) submitted to the Florida Fish and Wildlife Conservation Commission (FWC) were analysed using the lens of actor–network theory. The case study explores the intersection of conflicting stakeholder interests and types of knowledge, including how stakeholders variously defined the problem of user conflict in a coastal public space, and how they aligned themselves in relation to the problem and to each other. It further illustrates how shifting values and norms can intersect with changing technologies and environmental realities to produce new or increasing conflicts between natural resource user groups. This study underlines the importance and potential benefits of regulatory agencies explicitly and transparently engaging with value trade‐offs when managing conflicts among users of natural resources.

Interspecific interactions among three species of sea turtle using a common resting area.

Interspecific interactions among three species of sea turtle using a common resting area.

Response rate and content differences between web and mail surveys

AbstractThe Florida Fish and Wildlife Conservation Commission (Commission) conducts an annual harvest survey of licensed wild turkey (Meleagris gallopavo) hunters to determine the proportion of license holders that hunt and the estimated total harvest. The harvest survey is traditionally conducted with a mailed postcard, which is increasingly costly and time‐consuming to administer. The Commission has considered using a less costly and less protracted web‐based survey. From 2012 through 2014, we conducted web and mail surveys of licensed turkey hunters to compare response rates and reported rate of hunting participation. The average response rate differed between mail and web survey respondents (25.5% and 16.5%, respectively). Rates of hunting participation also differed between the survey modes; 40.5% and 61.4%, respectively, of mail and web survey respondents said that they hunted during the previous spring season. When hunting participation rates were extrapolated to the total number of license holders in the state, the projected average number of hunters across the 3 years was 17,356 (52%) greater from the web survey than the mail survey. Demographic weighting (age class, sex, ethnicity, median household income, or urbanicity) failed to account for the difference in reported hunting participation between survey modes. Our results indicated that respondents of the 2 survey modes differed fundamentally in either their hunting behavior or in their propensity to respond to the surveys, both of which have ramifications when management decisions are based on the results of harvest surveys. Although a mixed‐mode survey may be a feasible option to reduce cost and still obtain accurate harvest estimates, we caution against abruptly switching from mail to web surveys given the vastly different outcomes.

Characteristics, attitudes, and motivations of hunting mentors in Florida

AbstractAcross the United States, conservation leaders have been concerned about declines in hunting participation because hunting license sales and taxes on the sale of equipment used for hunting generate a significant portion of wildlife conservation funding. Natural resource agencies have begun focusing on recruitment, retention, and reactivation (R3) initiatives to reverse this decline. These initiatives, in part, seek to increase participation in hunting and shooting sports of currently nonhunting audiences. One of the primary techniques used by the R3 initiative is to develop mentoring programs that provide hunting opportunities for participants with an experienced hunter. Because of its unique and flexible tactics (e.g., calling, still hunting vs run and gun hunting), turkey hunting affords a natural opportunity for mentoring to take place. However, to make mentoring programs efficient and effective, R3 practitioners must have an understanding of the demographics of mentors and what challenges or incentives may exist to participating in a mentoring program. Therefore, we surveyed Florida turkey hunters to (1) understand the demographics of turkey hunters who mentor and (2) assess the challenges, benefits, and incentives to mentoring other turkey hunters in Florida. In 2015, we collected a random sample of 2,817 Florida hunters eligible to hunt turkeys from the Florida Fish and Wildlife Conservation Commission hunting license registry. A total of 710 respondents actively hunted turkeys in the state of Florida. Experienced turkey hunters who mentor perceived challenges (lack of time, interferes with their own hunting opportunity, unfamiliar with mentoring opportunities) less and viewed incentives less than novice and intermediate experienced mentoring hunters. Among wild turkey hunters in Florida, the propensity to mentor was greater among men and those who hunted private land and increased with level of turkey‐hunting experience. To recruit new mentors, agencies must increase awareness of formal mentor programs that focus a connection to public land access and provide recognition to the individuals attending.

Environmental Factors and Stock Abundance Influence Year‐Class Strength of Spotted Seatrout at Cedar Key, Florida

AbstractEnvironmental pressures can influence recruitment of estuarine fishes by impacting growth and survival of juveniles as well as adult habitat use and behavior. Identifying potential drivers of year‐class strength is an important tool for assessing stock health and implementing management decisions. The goal of this study was to determine how environmental factors and adult stock influence trends in recruitment of Spotted Seatrout Cynoscion nebulosus in Cedar Key, Florida. Juvenile indices of abundance were generated using sampling data from the Florida Fish and Wildlife Conservation Commission’s Fisheries‐Independent Monitoring program. Young‐of‐the‐year indices of abundance suggested that annual recruitment was variable in this system and declined throughout the majority of the 1996–2018 time series. Adult abundance and water temperature in the spawning season were the most significant variables in predicting Spotted Seatrout recruitment, and both had positive relationships with recruitment. Salinity and river discharge were not significant environmental variables in predicting year‐class strength of Spotted Seatrout in this study. Our results indicated that recruitment was associated with interannual changes in water temperature and adult abundance, which could be used to explore how Spotted Seatrout recruitment dynamics could vary for stock assessments, for management decisions, and as a result of warming waters due to climate change.

Impact of Oyster (Crassostrea virginica) Reef Restoration on Benthic Invertebrates and Coastal Birds in a Subtropical Estuary

In order to mitigate the degradation of eastern oyster (Crassostrea virginica) reefs in Mosquito Lagoon (ML) along the east coast of central Florida, oyster reef restoration efforts have been in place for over 14 years. These restored reefs are successful in terms of universal oyster metrics (i.e., density, shell height, reef height) and are similar to natural reefs. However, little is known about the impact of this restoration on bird populations. ML provides a habitat for many bird species, including several listed as “threatened” by the Florida Fish and Wildlife Conservation Commission. Many of these birds rely on oyster reefs for foraging and loafing habitats. As benthic invertebrates serve as an important food source for coastal birds, we monitored the abundances and diversity of these organisms on live, restored, and dead reefs. We collected sediment samples from the reef sites pre-restoration, and one month, six months, one year, two years, and three years post-restoration. We counted benthic invertebrates present in the sediment samples, and sorted them by taxa (polychaetes, amphipods, isopods, gastropods, bivalves, decapods). Benthic invertebrate abundances on restored reefs became similar to live reefs over time (species composition, density), indicating that the prey base on restored reefs was similar to that of live reefs within 6 months. A second objective of this study was to determine if restored oyster reefs reach the same abundances, foraging behaviors, and diversity of bird species on natural, live reefs. We conducted monthly bird surveys to assess bird utilization of live, restored, and dead reefs. After three years, the abundances, behaviors, and assemblages of birds on restored reefs were similar to live reefs.

Risk assessment of chanchita Cichlasoma dimerus (Heckel, 1840), a newly identified non-native cichlid fish in Florida

Risk assessment of chanchita Cichlasoma dimerus (Heckel, 1840), a newly identified non-native cichlid fish in Florida