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2D AND 3D SHAPE VARIATION AMONG ELASMOBRANCH OLFACTORY ROSETTES
Title
2D AND 3D SHAPE VARIATION AMONG ELASMOBRANCH OLFACTORY ROSETTES.
Creator
Clark, Aubrey E., Porter, Marianne E., Meredith, Tricia L., Florida Atlantic University, Department of Biological Sciences, Charles E. Schmidt College of Science
Abstract/Description
The functional impacts of olfactory rosette variation in elasmobranchs is unresolved. Our goal was to quantify rosette morphology and shape from 14 species using dissections, phylogenetic comparisons, and microCT imaging. We hypothesized that lamellar count and rosette shape (fineness ratio) would not scale with animal size, but internal rosette size variables must scale positively. We found that fineness ratio and lamellar counts varied significantly among species, and were positively...
Show moreThe functional impacts of olfactory rosette variation in elasmobranchs is unresolved. Our goal was to quantify rosette morphology and shape from 14 species using dissections, phylogenetic comparisons, and microCT imaging. We hypothesized that lamellar count and rosette shape (fineness ratio) would not scale with animal size, but internal rosette size variables must scale positively. We found that fineness ratio and lamellar counts varied significantly among species, and were positively correlated. The first two principal components of the pPCA explained 82% of the variation, with fineness ratio and lamellar count contributing the most. There were no significant differences between rosette structure or volume when comparing dissected values to in situ values obtained using diceCT. Based on our results, we hypothesize that variations in rosette shape and morphology will impact hydrodynamics and optimize odorant detection, and these data can be used to create 3D models for future hydrodynamic studies.
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Date Issued
2020
PURL
http://purl.flvc.org/fau/fd/FA00013591
Subject Headings
Elasmobranchs, Olfactory sensors, Morphology
Format
Document (PDF)
EFFECTIVENESS OF A MAGNETIC SHARK DETERRENT
Title
EFFECTIVENESS OF A MAGNETIC SHARK DETERRENT.
Creator
Jones, Laura, Kajiura, Stephen, Florida Atlantic University, Department of Marine Science and Oceanography, Charles E. Schmidt College of Science
Abstract/Description
This study examined the effectiveness of a magnetic shark deterrent, the SharkBanz® Zeppelin, and quantified the magnetic field it produces. A shark entering the magnetic field induces an electric field that is detectable by electroreceptors. This novel stimulus may deter sharks away from hooked fish. The magnitude declined rapidly with distance and reached the ambient geomagnetic field at 36-39 cm away. Zeppelin devices and non-magnetic controls were deployed with baited remote underwater...
Show moreThis study examined the effectiveness of a magnetic shark deterrent, the SharkBanz® Zeppelin, and quantified the magnetic field it produces. A shark entering the magnetic field induces an electric field that is detectable by electroreceptors. This novel stimulus may deter sharks away from hooked fish. The magnitude declined rapidly with distance and reached the ambient geomagnetic field at 36-39 cm away. Zeppelin devices and non-magnetic controls were deployed with baited remote underwater video systems, and the responses of sharks were recorded. There was a significant difference between the number of sharks deterred between the Zeppelin and control. The Zeppelin deterred sharks on 22% of their approaches in the effective range, whereas the control deterred them on 2.6% of their approaches. Although the device may be effective at deterring sharks and act as a mitigation strategy for shark depredation, tests with live fish that provide more sensory stimuli are needed.
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Date Issued
2024
PURL
http://purl.flvc.org/fau/fd/FA00014556
Subject Headings
Sharks, Elasmobranchs, Magnetic fields, Electromagnetics
Format
Document (PDF)
Reproductive biology of lamnoid sharks
Title
Reproductive biology of lamnoid sharks.
Creator
Gilmore, R. G., Harbor Branch Oceanographic Institute
Date Issued
1993
PURL
http://purl.flvc.org/FCLA/DT/3333192
Subject Headings
Sharks, Lamniformes, Reproductive biology, Embryonic development, Elasmobranchs
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)
Movement and Habitat Use of Whitespotted Eagle Rays, Aetobatus narinari, throughout Florida
Title
Movement and Habitat Use of Whitespotted Eagle Rays, Aetobatus narinari, throughout Florida.
Creator
DeGroot, Breanna Clarice, Ajemian, Matthew, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
Abstract/Description
Elasmobranchs play ecologically important roles in coastal environments. Unfortunately, the basic distribution and movement patterns of these species, particularly rays, remain relatively unknown. This is especially true for the Whitespotted Eagle Ray (Aetobatus narinari), a protected species in Florida with poorly described migratory and habitat use patterns. I employed a combination of acoustic telemetry techniques to reveal multi-scale spatial patterns of A. narinari around Florida....
Show moreElasmobranchs play ecologically important roles in coastal environments. Unfortunately, the basic distribution and movement patterns of these species, particularly rays, remain relatively unknown. This is especially true for the Whitespotted Eagle Ray (Aetobatus narinari), a protected species in Florida with poorly described migratory and habitat use patterns. I employed a combination of acoustic telemetry techniques to reveal multi-scale spatial patterns of A. narinari around Florida. Movement patterns between the east and west coast individuals were distinct; a majority of west coast tagged A. narinari exhibited migratory or transient behavior while most east coast tagged individuals remained resident in the Indian River Lagoon. Fine-scale tracking of A. narinari revealed individuals spent a large percentage of time in the inlets and channels and frequently reused habitats parallel to the shore. This study fills a knowledge gap on the species ecology which may be used for adaptive management strategies throughout A. narinari’s range.
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Date Issued
2018
PURL
http://purl.flvc.org/fau/fd/FA00013116
Subject Headings
Aetobatus narinari, Spotted eagle ray, Chondrichthyes--Ecology, Elasmobranchs, Biotelemetry, Acoustic telemetry
Format
Document (PDF)