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Full-Text Articles in Marine Biology

Determination Of Atlantic Shortfin Mako Shark (Isurus Oxyrinchus) Population Genetic Structure And Comparison Of Mitogenomic Markers, Marissa Mehlrose Aug 2022

Determination Of Atlantic Shortfin Mako Shark (Isurus Oxyrinchus) Population Genetic Structure And Comparison Of Mitogenomic Markers, Marissa Mehlrose

All HCAS Student Capstones, Theses, and Dissertations

This study provides the first genomics-level, population structure and genetic diversity assessment of the shortfin mako (Isurus oxyrinchus) shark. The assessments were based on mitogenome sequences from makos distributed throughout the Atlantic Ocean, with Pacific mako mitogenomes used as a comparative outgroup. In addition to complete mitogenome-based analyses, I assessed individual mitochondrial coding gene and non-coding (Control Region) sequences for their comparative resolution properties as markers for revealing matrilineal population structure and genetic diversity. Sequencing of 125 makos in the western and eastern Atlantic across northern and southern hemispheres yielded 92 complete mitogenomes (16,698-16,702 bp) and 33 partial …


Genetic Population Dynamics Of The Critically Endangered Scalloped Hammerhead Shark (Sphyrna Lewini) In The Eastern Tropical Pacific Ocean, Sydney P. Harned Aug 2021

Genetic Population Dynamics Of The Critically Endangered Scalloped Hammerhead Shark (Sphyrna Lewini) In The Eastern Tropical Pacific Ocean, Sydney P. Harned

All HCAS Student Capstones, Theses, and Dissertations

The scalloped hammerhead shark, Sphyrna lewini, is a Critically Endangered, migratory species known for its tendency to form large aggregations of mostly adult females, especially in the heavily-fished Eastern Tropical Pacific (ETP) Ocean. This species forms iconic, visually spectacular, seasonal aggregations in the northern Galápagos Islands, and it is hypothesized based on telemetry studies that pregnant females from these aggregations migrate to mainland coastal nurseries for parturition. This study investigated the population genetic dynamics of the scalloped hammerhead across most of its coastal and offshore distribution (Mexico to Ecuador) in the ETP, focusing on young-of-the-year animals sampled from nursery …


Comparisons Of Five Dna Repair Pathways Between Elasmobranch Fishes And Humans, Lucia Llorente Jan 2019

Comparisons Of Five Dna Repair Pathways Between Elasmobranch Fishes And Humans, Lucia Llorente

HCNSO Student Theses and Dissertations

Although DNA repair capacity has been correlated with lifespan in terrestrial vertebrate species, it remains unknown how evolutionarily conserved the process is across all vertebrate taxa. In particular, chondrichthyan fishes have lifespans that range from 3-350 years and they are evolutionarily separated from modern humans Homo sapiens by approximately 400 million years. We hypothesized that chondrichthyan fishes would show significant homology in nuclear excision repair (NER) genes with humans, and that the expression of NER genes will correlate with the lifespan of the respective assessed species. For this study, DNA repair gene homology and expression was performed on the nurse …


Meta-Analytic Summary Of Parasites And Diseases Of Elasmobranchs Found In Florida Waters, Alexis S. Modzelesky Aug 2018

Meta-Analytic Summary Of Parasites And Diseases Of Elasmobranchs Found In Florida Waters, Alexis S. Modzelesky

HCNSO Student Capstones

Elasmobranchs have conservational and commercial importance. There is a need for a more complete understanding of their health, due to their ability to shape trophic webs and their money-making potential with fishers and ecotourists. Sharks have been known to influence the strength of food webs, including reef ecosystems where many fish species are harvested for food. The investigation of pathogenic agents and diseases in elasmobranchs has been biased to favor those natural enemies that inhabit the digestive system and epidermal surfaces. Certain groups of parasites such as cestodes, copepods, and monogeneans, were most often recorded in this study. The bacterial …


Genetic Population And Evolutionary Dynamics Of The Angel Sharks, Squatina Spp., Cristin Keelin Fitzpatrick May 2018

Genetic Population And Evolutionary Dynamics Of The Angel Sharks, Squatina Spp., Cristin Keelin Fitzpatrick

HCNSO Student Theses and Dissertations

Once so abundant as to be called the ‘common’ angelshark, Squatina squatina has been extirpated from nearly the entirety of its historical range, from the eastern North Atlantic, to the Mediterranean Sea [International Union for the Conservation of Nature (IUCN) Red List: Critically Endangered]. The angelshark now only occurs in any abundance in the waters surrounding the Canary Islands. I present the first genetic assessment of the angelshark’s population dynamics and diversity from three locations within the Canary Islands archipelago: Gran Canaria, Tenerife, and Lanzarote. Using a suite of individual mitochondrial genome regions [Control region (CR), NADH dehydrogenase subunit 2 …


Microbial Community Richness Distinguishes Shark Species Microbiomes In South Florida, Rachael Cassandra Karns Jul 2017

Microbial Community Richness Distinguishes Shark Species Microbiomes In South Florida, Rachael Cassandra Karns

HCNSO Student Theses and Dissertations

The microbiome (microbial community) of individuals is crucial when characterizing and understanding processes that are required for organism function and survival. Microbial organisms, which make up an individual’s microbiome, can be linked to disease or function of the host organism. In humans, individuals differ substantially in their microbiome compositions in various areas of the body. The cause of much of the composition diversity is yet unexplained, however, it is speculated that habitat, diet, and early exposure to microbes could be altering the microbiomes of individuals (Human Microbiome Project Consortium, 2012b, 2012a). To date, only one study has reported on microbiome …


Estimating Growth And Mortality In Elasmobranchs: Are We Doing It Correctly?, Brian J. Moe Apr 2015

Estimating Growth And Mortality In Elasmobranchs: Are We Doing It Correctly?, Brian J. Moe

HCNSO Student Theses and Dissertations

The instantaneous mortality rate (M) is an important parameter in elasmobranch management and conservation, but is difficult to estimate directly. Thus, indirect estimates based on relatively easily obtained life history parameters are commonly used. Many indirect methods incorporate one or more parameters from the von Bertalanffy growth model (VBGM), which is often criticized for its inability to describe changes in growth associated with maturity. The Lester growth model (LGM) is a biphasic alternative to the VBGM that incorporates trade-offs between reproduction, growth, and survival, and may therefore more accurately estimate M. I used published data from 29 …


Combined Gut Content-Stable Isotope Trophic Analysis And Satellite Tagging Of The Pelagic Stingray Pteroplaytrygon Violacea (Bonaparte, 1832) From The Western North Atlantic Ocean, Tiffany A. Weidner Apr 2014

Combined Gut Content-Stable Isotope Trophic Analysis And Satellite Tagging Of The Pelagic Stingray Pteroplaytrygon Violacea (Bonaparte, 1832) From The Western North Atlantic Ocean, Tiffany A. Weidner

HCNSO Student Theses and Dissertations

The pelagic stingray, Pteroplatytrygon violacea, is a bycatch species in the global pelagic longline fishery. However, little research has been conducted on its basic biology, including prey composition, trophic positioning, and habitat utilization. Descriptions of the habitat utilization have largely been through indirect analyses of catch rates in commercial fisheries, which also provided no information on actual behaviors. The first chapter of this thesis will describe the habitat utilization and behavior of four individual pelagic stingrays using electronic tagging technology. Prior diet descriptions were hampered, in part, by low sample sizes and accordingly provided little information on the ecological …