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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)