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This research focuses on the economic component of a bioeconomic model for spotted seatrout in the recreational fisheries on Florida's west coast. A survey was designed to assess how anglers, who caught or targeted spotted seatrout on Florida's west coast, valued combined changes in the existing bag limit and size limit. The biological component of the stated preference model deemed such change necessary to ensure a sustainable stock. The biological model provides an economic constraint and results in the treatment of the bag and size limits as a composite good in which separate utilities cannot be measured for each component of the composite good. The stated preference choice method (SPCM) was used to estimate the change in economic value by boat mode of access (e.g., charter boat and private boat). The models also controlled for length of trip (full day versus half-day) for charter boat trips and for type of day (weekend or weekday) for both boat modes of access. Since those who accessed the fishery by private boat had a lower probability of achieving the bag limit/size limit, a model was run to predict the probability of achieving the bag limit/size limit and the probability was interacted with the bag limit/size limit choice. This yielded a positive willingness to pay for the bag limit/size limit combination that was sustainable. Estimated values per person per day for changing the bag limit/size limits to a sustainable level were USD 20.24 for the charter boat mode and USD 32.54 for the private boat mode. Aggregating this to a total value change using a five-year annual average (2012–2016) of total days of fishing for spotted seatrout on Florida's West Coast yielded an estimate of USD 147.9 million per year for charter boat anglers. The total annual value was about USD 3.4 million, while for private boat anglers the annual value was about USD 144.5 million. [ABSTRACT FROM AUTHOR]

Age‐ or length‐structured stock assessments require reliable life history demographic parameters (growth, mortality, reproduction) to model population dynamics, potential yields and stock sustainability. This study synthesized life history information for 84 commercially exploited tropical reef fish species from Florida and the U.S. Caribbean (Puerto Rico and the U.S. Virgin Islands). We attempted to identify a useable set of life history parameters for each species that included lifespan, length at age, weight at length and maturity at length. Key aspects of the life history synthesis were development of: (a) a database that characterized study details including sampling region, biological and statistical methods, length range of sampled individuals, sample size, capture gears and sampling time frame; (b) reproducible procedural criteria for parameter identification for a given species; and (c) a reliability metric for each parameter type. Complete life history parameter sets were available for 46 species analysed. Of these, only 16 species had parameter sets meeting the highest standards for reliability, highlighting future research needs. [ABSTRACT FROM AUTHOR]

Exploitation impacts and management options for 15 coral reef fish species central to the commercial and recreational fisheries of the southern Florida USA coral reef ecosystem were evaluated using a length-based risk analysis (LBRA) framework. Population abundance-at-length composition data were obtained from several regional federal-state sampling programs. These and updated life history demographic data were integrated into a length-based numerical cohort model to generate LBRA fishery sustainability metrics from a probabilistic perspective. Three of five groupers, eight of eight snappers, and two of two grunts were below the 40% spawning potential ratio (SPR) stock sustainability minimum; ten of these stocks are at < 20% of their historical spawning biomass, some as low as 5%. Therefore, to ameliorate overfishing for the 13 stocks with sustainability risks ≥ 98%, fisheries management requires increased minimum sizes of first capture L c and significant reductions in fishing mortality F . To achieve sustainability and reduce sustainability risks area-time protections are also needed. While lack of data often limits the evaluation of management options, this paper establishes benchmarks from which data-limited approaches can move forward. In addition, the approach can be used to cross-check other data-rich analyses. A goal of this work is to effectively balance sustainability risks with fishery production to mitigate overfishing likelihoods and to increase the probability of sustainable fisheries. [ABSTRACT FROM AUTHOR]

Abstract: The efficacy of no-take marine reserves (NTMRs) to enhance and sustain regional coral reef fisheries was assessed in Dry Tortugas, Florida, through 9 annual fishery-independent research surveys spanning 2 years before and 10 years after NTMR implementation. A probabilistic sampling design produced precise estimates of population metrics of more than 250 exploited and non-target reef fishes. During the survey period more than 8100 research dives utilizing SCUBA Nitrox were optimally allocated using stratified random sampling. The survey domain covered 326km2, comprised of eight reef habitats in four management areas that offered different levels of resource protection: the Tortugas North Ecological Reserve (a NTMR), Dry Tortugas National Park (recreational angling only), Dry Tortugas National Park Research Natural Area (a NTMR), and southern Tortugas Bank (open to all types of fishing). Surveys detected significant changes in population occupancy, density, and abundance within management zones for a suite of exploited and non-target species. Increases in size, adult abundance, and occupancy rates were detected for many principal exploited species in protected areas, which harbored a disproportionately greater number of adult spawning fishes. In contrast, density and occupancy rates for aquaria and non-target reef fishes fluctuated above and below baseline levels in each management zone. Observed decreases in density of exploited species below baseline levels only occurred at the Tortugas Bank area open to all fishing. Our findings indicate that these NTMRs, in conjunction with traditional fishery management control strategies, are helping to build sustainable fisheries while protecting the fundamental ecological dynamics of the Florida Keys coral-reef ecosystem. [Copyright &y& Elsevier]

The article discusses the results of a study that examines the appearance and rapid spread of Indo-Pacific lionfishes, Pterois volitans and Pterois miles in the Florida Keys in 2009. The study quantifies the invasion of lionfishes in a new area by the use of multiple monitoring data sets. It observes the rapid increase in the lionfish frequency of occurrence, abundance and biomass between 2009 and 2011.

Abstract: Principles of statistical sampling design were used to guide refinement of a 30-year multispecies fishery-independent diver visual survey of population abundance and size structure of more than 250 exploited and non-target fishes in the Florida coral reef ecosystem. Reef habitat features and no-take marine reserves (NTMRs) were used to partition the 885km2 sampling domain into sub-areas (or strata) to control the variation of fish density. For the period 1999–2008, survey precision of population density and abundance (CV, coefficient of variation, ratio of standard error to mean) ranged from 7% to 20% for the majority of 13 primary exploited species in the Florida Keys and Dry Tortugas regions. Population sustainability metrics like species average length in the exploited life stage were comparable between our fishery-independent survey and fishery-dependent catch-sampling. The survey design also performed well for non-target fishes, yielding CVs between 6% and 15% for population density for the majority of 36 species. Sampling efficiency was improved over time via an iterative learning process by which past survey data was used to refine the stratification and allocation schemes of future surveys. We show how survey data are used to support multispecies stock assessments, evaluate the effectiveness of NTMRs, and assess ecosystem condition for the reef fish community. [Copyright &y& Elsevier]

The article focuses on the development of sustainable fisheries in the coral reef ecosystem of Dry Tortugas, Florida. The 267 fishes in the area are stable and the reef-fish biodiversity is high. No-take marine reserves can help develop sustainable fisheries and at the same time, it can protect the coral-reef ecosystem of Florida Keys.

Focuses on the adoption of an ecosystem-based perspective to asses and improve sustainable multispecies coral reef fisheries in the Florida Keys, Florida. Evaluation of marine reserve boundary options; Details on the dynamics of exploited fish stocks; Exploration of inter-related management issues involving fishery exploitation.

Concern about declining trends in coral reef habitats and reef fish stocks in the Florida Keys contributed to the implementation of a network of no-take marine protected areas in 1997. In support of the efforts of the Dry Tortugas National Park and Florida Keys National Marine Sanctuary to implement additional no-take areas in the Tortugas region in 2001, we expanded the scale of our fisheries independent monitoring program for coral reef fishes in the region. To provide a foundation for the habitat-based, stratified random sampling design of the program, we created a digital benthic habitat map of coral reef and hard-bottom habitats in a geographic information system by synthesizing data from bathymetric surveys, side-scan sonar imagery, aerial photogrammetry, existing habitat maps, and in situ visual surveys. Existing habitat maps prior to 1999 were limited to shallow-water (< 20 m depth) soft-sediment, coral reef, and hard-bottom habitats within Dry Tortugas National Park and did not include deeper areas such as the Tortugas Bank, now partially contained within no-take marine protected area boundaries. From diver observations made during the 1999 survey, we developed a classification scheme based on habitat relief and patchiness to describe nine hard-bottom and coral reef habitats encountered from 1-33 m depth. We provide estimates of area by habitat type for no-take marine protected areas in the Tortugas region. Updated information on the spatial distribution and characteristics of benthic habitats will be used to guide future monitoring, assessment, and management activities in the region. Significant data gaps still exist for the western area of the Florida Keys National Marine Sanctuary and are a priority for future research. [ABSTRACT FROM AUTHOR]

The Anthropocene rise in global temperatures is facilitating the expansion of tropical species into historically non-native subtropical locales, including coral reef fish. This redistribution of species, known as tropicalization, has serious consequences for economic development, livelihoods, food security, human health, and culture. Measuring the tropicalization of subtropical reef fish assemblages is difficult due to expansive species ranges, temporal distribution shifts with the movement of isotherms, and many dynamic density-dependent factors affecting occurrence and density. Therefore, in locales where tropical and subtropical species co-occur, detecting tropicalization changes relies on regional analyses of the relative densities and occurrence of species. This study provides a baseline for monitoring reef fish tropicalization by utilizing extensive monitoring data from a pivotal location in southeast Florida along a known transition between tropical and subtropical ecotones to define regional reef fish assemblages and use benthic habitat maps to spatially represent their zoogeography. Assemblages varied significantly by ecoregion, habitat depth, habitat type, and topographic relief. Generally, the southern assemblages had higher occurrences and densities of tropical species, whereas the northern assemblages had a higher occurrence and density of subtropical species. A total of 108 species were exclusive to regions south of the Bahamas Fracture Zone (BFZ) (South Palm Beach, Deerfield, Broward-Miami) and 35 were exclusive to the north (North Palm Beach, Martin), supporting the BFZ as a pivotal location that affects the coastal biogeographic extent of tropical marine species in eastern North America. Future tropicalization of reef fish assemblages are expected to be evident in temporal deviance of percent occurrence and/or relative species densities between baseline assemblages, where the poleward expansion of tropical species is expected to show the homogenization of assemblage regions as adjacent regions become more similar or the regional boundaries expand poleward. Ecoregions, habitat depth, habitat type, and relief should be incorporated into the stratification and analyses of reef fish surveys to statistically determine assemblage differences across the seascape, including those from tropicalization., (© 2024. The Author(s).)

Principles of probability survey design were applied to guide large-scale sampling of populations of stony corals and associated benthic taxa in the Florida Keys coral reef ecosystem. The survey employed a two-stage stratified random sampling design that partitioned the 251-km(2) domain by reef habitat types, geographic regions, and management zones. Estimates of the coefficient of variation (ratio of standard error to the mean) for stony coral population density and abundance ranged from 7% to 12% for four of six principal species. These levels of survey precision are among the highest reported for comparable surveys of marine species. Relatively precise estimates were also obtained for octocoral density, sponge frequency of occurrence, and benthic cover of algae and invertebrates. Probabilistic survey design techniques provided a robust framework for estimating population-level metrics and optimizing sampling efficiency.