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THREE-DIMENSIONAL MOVEMENT AND HABITAT USE OF YOUNG WHITE SHARKS (CARCHARODON CARCHARIAS) IN THE NORTHWEST ATLANTIC OCEAN
Title
THREE-DIMENSIONAL MOVEMENT AND HABITAT USE OF YOUNG WHITE SHARKS (CARCHARODON CARCHARIAS) IN THE NORTHWEST ATLANTIC OCEAN.
Creator
Shaw, Rachel Lynn, Ajemian, Matthew, Florida Atlantic University, Department of Biological Sciences, Charles E. Schmidt College of Science
Abstract/Description
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...
Show moreRecent 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.
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Date Issued
2020
PURL
http://purl.flvc.org/fau/fd/FA00013440
Subject Headings
Carcharodon carcharias, White shark, Marine nurseries, Sharks--Ecology
Format
Document (PDF)
Characterization of Elasmobranch Community Dynamics in the Indian River Lagoon
Title
Characterization of Elasmobranch Community Dynamics in the Indian River Lagoon.
Creator
Roskar, Amelia Grace, Ajemian, Matthew, Florida Atlantic University, Charles E. Schmidt College of Science, Depament of Biological Sciences
Abstract/Description
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...
Show moreFlorida’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.
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Date Issued
2019
PURL
http://purl.flvc.org/fau/fd/FA00013256
Subject Headings
Indian River (Fla : Lagoon)--Environmental conditions, Elasmobranchs, Sharks--Ecology, Rays (Fishes)--Ecology
Format
Document (PDF)
Ecomorphology of Shark Electroreceptors
Title
Ecomorphology of Shark Electroreceptors.
Creator
Cornett, Anthony D., Kajiura, Stephen M., Florida Atlantic University
Abstract/Description
Sharks possess an electrosensory system which allows the detection of electric fields . How this system varies among related taxa and among species inhabiting different environments remains unexplored. Electroreceptor number was quantified for representative species of related taxa (genera, families, orders) from different environments (pelagic, coastal, deepwater) and taxa from similar environments to determine potential phylogenetic constraint or evolutionary convergence. Coastal open water...
Show moreSharks possess an electrosensory system which allows the detection of electric fields . How this system varies among related taxa and among species inhabiting different environments remains unexplored. Electroreceptor number was quantified for representative species of related taxa (genera, families, orders) from different environments (pelagic, coastal, deepwater) and taxa from similar environments to determine potential phylogenetic constraint or evolutionary convergence. Coastal open water sharks possess the greatest number of electroreceptors; deepwater sharks the least. Pelagic and coastal benthic sharks retain comparable electrosensory pore numbers despite inhabiting vastly different environments. Electrosensory pores were primarily located in ventral distributions, except among coastal open water sharks which possess roughly even distributions around the head. Among related species and genera, pore numbers and distribution are comparable, with greater variation among higher taxa. Results implicate evolutionary convergence as the primary influence in electroreceptor development, while phylogenetic constraint establishes similar base values for number and distribution.
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Date Issued
2006
PURL
http://purl.flvc.org/fau/fd/FA00000737
Subject Headings
Sharks--Ecology, Sharks--Morphology, Echolocation (Physiology), Aquatic animals--Physiology, Senses and sensation, Adaptation (Biology)
Format
Document (PDF)
Jaws of significance
Title
Jaws of significance: the conservationist's perception of the shark in South Florida.
Creator
Nason, Patrick., Dorothy F. Schmidt College of Arts and Letters, Department of Anthropology
Abstract/Description
In examining the intentional relationship between the conservationist and the shark in South Florida, this thesis considers the latter as both a scarce natural resource - caught up in what Clifford Geertz citing Weber referred to as "webs of significance" (Geertz 1973:5) - and as a reflection of dynamic human conceptions of nature : a meta shark. This complex relationship is described by interpretations of conservation discourse recorded through ethnographic interviews that demonstrate how...
Show moreIn examining the intentional relationship between the conservationist and the shark in South Florida, this thesis considers the latter as both a scarce natural resource - caught up in what Clifford Geertz citing Weber referred to as "webs of significance" (Geertz 1973:5) - and as a reflection of dynamic human conceptions of nature : a meta shark. This complex relationship is described by interpretations of conservation discourse recorded through ethnographic interviews that demonstrate how these perceptions have been influenced by factors such as personal experiences, film and text, and broad changes in the relationship between humans and nature since the early days of the environmental movement. By linking these perceptual changes with changes in American shark conservation policy, this work not only explains a relationship between culture, perception, and policy, but also celebrates the emergence of a multispecies marine community.
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Date Issued
2012
PURL
http://purl.flvc.org/FAU/3358755
Subject Headings
Sharks, Conservation, Predation (Biology), Wildlife conservation, Aquatic resources conservation, Marine animals, Ecology, Human-animal relationships
Format
Document (PDF)
Pelvic fin locomotion in batoids
Title
Pelvic fin locomotion in batoids.
Creator
Macesic, Laura Jane., Charles E. Schmidt College of Science, Department of Biological Sciences
Abstract/Description
Although most batoids (skates and rays) are benthic, only the skates (Rajidae) have been described as performing benthic locomotion, termed 'punting'. While keeping the rest of the body motionless, the skate's specialized pelvic fins are planted into the substrate and then retracted caudally, which thrusts the body forward. This may be advantageous for locating and feeding on prey, avoiding predators, and reducing energetic costs. By integrating kinematic, musculoskeletal, material properties...
Show moreAlthough most batoids (skates and rays) are benthic, only the skates (Rajidae) have been described as performing benthic locomotion, termed 'punting'. While keeping the rest of the body motionless, the skate's specialized pelvic fins are planted into the substrate and then retracted caudally, which thrusts the body forward. This may be advantageous for locating and feeding on prey, avoiding predators, and reducing energetic costs. By integrating kinematic, musculoskeletal, material properties, and compositional analyses across a range of morphologically and phylogenetically diverse batoids, this dissertation (i) demonstrates that punting is not confined to the skates, and (ii) provides reliable anatomical and mechanical predictors of punting ability. Batoids in this study performed true punting (employing only pelvic fins), or augmented punting (employing pectoral and pelvic fins). Despite the additional thrust from the pectoral fins, augmented punters failed to exceed the punting c apabilities of the true punters. True punters' pelvic fins had greater surface area and more specialized and robust musculature compared to the augmented punters' fins. The flexural stiffness of the main skeletal element used in punting, the propterygium, correlated with punting ability (3.37 x 10-5 - 1.80 x 10-4 Nm2). Variation was due to differences in mineral content (24.4-48-9% dry mass), and thus, material stiffness (140-2533 MPa), and second moment of area. The propterygium's radius-to-thickness ratio (mean = 5.52 +-0.441 SE) indicated that the propterygium would support true and augmented punters, but not non-punters, in an aquatic environment. All propterygia would fail on land. Geometric and linear morphometric analyses of 61 batoid pelvic girdles demonstrated that pelvic girdle shape can predict punting and swimming ability and taxonomic attribution to Order., Characteristics of true punters' pelvic girdles, such as laterally facing fin articulations, large surface area formuscle attachment, and tall lateral pelvic processes are similar to characteristics of early sprawled-gait tetrapods' pelvic girdles. This dissertation demonstrates that punting is common in batoids, illustrates the convergent evolution of true punter and early tetrapod pelvic anatomy, and gives possible explanations for the restriction of elasmobranchs to aquatic habitats.
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Date Issued
2011
PURL
http://purl.flvc.org/FAU/3171678
Subject Headings
Sharks, Ecology, Fins, Anatomy, Adaptation (Biology), Aquatic animals, Physiology, Fishes, Locomotion
Format
Document (PDF)