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Bonefish Albula vulpes are an economically important sport fish that has historically bolstered the recreational flats fisheries of the Florida Keys and The Bahamas; an industry with an annual economic impact of US$465 million and US$169 million, respectively. Analyses of fishing guide logbooks and guide interviews indicate that the population of bonefish in south Florida has declined. Due to the economic and cultural importance of these fisheries, protection of spawning and nursery habitats is integral to population recovery and stability. However, knowledge gaps persist in how abiotic and biotic habitat factors influence reproduction and recruitment. Without clear delineation of spawning and recruitment habitats, bonefish populations remain vulnerable to anthropogenic disturbances. Bonefish partake in a unique three-point spawning migration, migrating from shallow-water home flats to form nearshore pre-spawning aggregations (PSA) before moving offshore to spawn. Using active acoustic telemetry, sonar imagery, and CTD profiles, the first complete account of offshore spawning movements and novel deep diving behavior was accomplished. Bonefish reached depths of 137.9 m and spawned at 67.3 m, a depth associated with the pycnocline/thermocline. Previous efforts show spatiotemporal plasticity in spawning, a behavior counter to other aggregation forming fishes., 2022, Includes bibliography., Degree granted: Dissertation (Ph.D.)--Florida Atlantic University, 2022., Collection: FAU Electronic Theses and Dissertations Collection

Offshore platforms, subsea pipelines, wells and related fixed structures supporting the oil and gas (O&G) industry are prevalent in oceans across the globe, with many approaching the end of their operational life and requiring decommissioning. Although structures can possess high ecological diversity and productivity, information on how they interact with broader ecological processes remains unclear. Here, we review the current state of knowledge on the role of O&G infrastructure in maintaining, altering or enhancing ecological connectivity with natural marine habitats. There is a paucity of studies on the subject with only 33 papers specifically targeting connectivity and O&G structures, although other studies provide important related information. Evidence for O&G structures facilitating vertical and horizontal seascape connectivity exists for larvae and mobile adult invertebrates, fish and megafauna; including threatened and commercially important species. The degree to which these structures represent a beneficial or detrimental net impact remains unclear, is complex and ultimately needs more research to determine the extent to which natural connectivity networks are conserved, enhanced or disrupted. We discuss the potential impacts of different decommissioning approaches on seascape connectivity and identify, through expert elicitation, critical knowledge gaps that, if addressed, may further inform decision making for the life cycle of O&G infrastructure, with relevance for other industries (e.g. renewables). The most highly ranked critical knowledge gap was a need to understand how O&G structures modify and influence the movement patterns of mobile species and dispersal stages of sessile marine species. Understanding how different decommissioning options affect species survival and movement was also highly ranked, as was understanding the extent to which O&G structures contribute to extending species distributions by providing rest stops, foraging habitat, and

Shellfish aquaculture “grow-out” sites for Northern Quahog (Mercenaria mercenaria) clams have substantially higher densities than the surrounding ambient environment and thus can attract local molluscivores to these areas. I used acoustic telemetry to examine potential interactions of two highly mobile ray species (cownose ray, whitespotted eagle ray) with two clam grow-out sites in the Indian River Lagoon near Sebastian, FL, where clammers have reported damaged grow-out gear. Visitation patterns of telemetered rays to these sites were compared to other reference sites in the region and modeled using local environmental data. While both species spent greater time elsewhere, I found many instances in which rays remained within range of clam grow-out sites for extended periods (>60 minutes). Mesocosm experiments with whitespotted eagle rays confirmed they were capable of interacting with and damaging clams housed within antipredator materials, although mortality was significantly reduced compared to controls and in particular by multi-layer netting., 2021, Includes bibliography., Degree granted: Thesis (MS)--Florida Atlantic University, 2021., Collection: FAU Electronic Theses and Dissertations Collection

Recent research confirmed white shark (Carcharodon carcharias) nursery habitat off Long Island, New York; however, additional research is required to determine the habitat use and fine-scale movements of young-of-the-year and juvenile white sharks within this nursery. Between 2016 and 2019, twenty-five white sharks were fitted with satellite and acoustic tags to better define habitat use. Individuals exhibited horizontal movements parallel to Long Island’s southern shoreline and coastal New Jersey. Log-likelihood chi-square analyses determined preference for water column depth, SSTs, sea surface salinities, and chlorophyll a concentration. Vertical analysis of diving behavior revealed swimming behavior primarily in the upper 20 m of the water column, in temperatures between 18°C and 20°C. Generalized additive mixed modeling suggested SSTs above 20.5°C affected dive depth. These results can help improve characterization of essential fish habitat for young white sharks and provide data to determine the species’ susceptibility to anthropogenic activities., 2020, Includes bibliography., Degree granted: Thesis (M.S.)--Florida Atlantic University, 2020., Collection: FAU Electronic Theses and Dissertations Collection

Florida’s Indian River Lagoon (IRL) has experienced myriad anthropogenic impacts and knowledge on elasmobranchs (sharks and rays) in the southern IRL is lacking. A fishery independent survey (longline/gillnet) was implemented to 1) assess the effects of bait type [striped mullet (Mugil cephalus) versus Atlantic mackerel (Scomber scombrus)] and mesh size (15.2 cm versus 20.3 cm stretch mesh) on elasmobranch species composition, catch-per-unit effort, and size distributions and 2) characterize elasmobranch abundance and distribution. From 2016 - 2018, 630 individuals (16 species) were captured, more often in the gillnet than the longline. Catch-per-unit-effort was significantly higher with mullet than mackerel. Species composition differed among gears. Although dependent on gear, there was evidence of seasonal and spatial patterns in abundance and species composition. This study provides the first baseline abundance indices for many elasmobranchs in the IRL and develops the capacity to understand how elasmobranchs may respond to changes in this highly modified estuary., 2019, Includes bibliography., Degree granted: Thesis (M.S.)--Florida Atlantic University, 2019., Collection: FAU Electronic Theses and Dissertations Collection