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Full-Text Articles in Life Sciences

Seasonal Abundance Of The Nudibranch Dondice Jupiteriensis On The Colonial Hydroid Eudendrium Carneum, Erika Molina, Daniela Gutierrez-Andrade, Samantha Schlegel, Julia Piper, Louis J. Ambrosio, Michael L. Middlebrooks Jan 2024

Seasonal Abundance Of The Nudibranch Dondice Jupiteriensis On The Colonial Hydroid Eudendrium Carneum, Erika Molina, Daniela Gutierrez-Andrade, Samantha Schlegel, Julia Piper, Louis J. Ambrosio, Michael L. Middlebrooks

Gulf and Caribbean Research

Benthic colonial hydroids often serve as a host to a large variety of invertebrate taxa. The colonial hydroid Eudendrium carneum Clarke, 1882 is host to a variety of epifauna, including the recently described nudibranch Dondice jupiteriensis García—Méndez & Valdés, 2022. Like many species of heterobranch sea slugs, little is known about the natural history and population biology of D. jupiteriensis. Here we describe a year—long study recording the population density and size structure of D. jupiteriensis on E. carneum colonies in Tampa Bay, FL USA. We found that the D. jupiteriensis population persists year—round but is the densest during …


Biophysical Factors Affecting Habitat Suitability For Crassostrea Virginica, Jason D. Tilley Dec 2023

Biophysical Factors Affecting Habitat Suitability For Crassostrea Virginica, Jason D. Tilley

Dissertations

Oyster reefs provide a variety of important ecosystem services. However, the mortality rate of eastern oyster, Crassostrea virginica, the dominant species that produces oyster reefs in the northern Gulf of Mexico, is increasing at an alarming rate due to a variety of abiotic and biological factors. I examined how biophysical factors, including the less-studied fatty acid profiles of the suspended particulate matter on which oysters feed, influenced morphometric condition of C. virginica.

I sampled suspended particulate matter (SPM) and oysters in-situ in the western Mississippi Sound, which historically supported the majority of oyster production in Mississippi waters. Sampling …


Interactive Effects Of Climate Change‐Induced Range Shifts And Wind Energy Development On Future Economic Conditions Of The Atlantic Surfclam Fishery, Stephanie Stromp, Andrew M. Scheld, John M. Klinck, Daphne M. Munroe, Eric N. Powell, Roger Mann, Sarah Borsetti, Eileen E. Hofmann Apr 2023

Interactive Effects Of Climate Change‐Induced Range Shifts And Wind Energy Development On Future Economic Conditions Of The Atlantic Surfclam Fishery, Stephanie Stromp, Andrew M. Scheld, John M. Klinck, Daphne M. Munroe, Eric N. Powell, Roger Mann, Sarah Borsetti, Eileen E. Hofmann

Faculty Publications

Rising water temperatures along the northeastern U.S. continental shelf have resulted in an offshore range shift of the Atlantic surfclam Spisula solidissima to waters still occupied by ocean quahogs Arctica islandica. Fishers presently are prohibited from landing both Atlantic surfclams and ocean quahogs in the same catch, thus limiting fishing to locations where the target species can be sorted on deck. Wind energy development on and around the fishing grounds will further restrict the fishery. A spatially explicit model of the Atlantic surfclam fishery (Spatially Explicit Fishery Economics Simulator) has the ability to simulate the consequences of fishery displacement …


The Influence Of Range Shifts And Wind Energy On The Atlantic Surfclam (Spisula Solidissima) And Ocean Quahog (Arctica Islandica) Fisheries On The U.S. Outer Continental Shelf, Stephanie Stromp Mar 2023

The Influence Of Range Shifts And Wind Energy On The Atlantic Surfclam (Spisula Solidissima) And Ocean Quahog (Arctica Islandica) Fisheries On The U.S. Outer Continental Shelf, Stephanie Stromp

Master's Theses

The Atlantic surfclam, Spisula solidissima, is a biomass dominant bivalve of the Northwestern Atlantic. The surfclam’s historic range extended from Cape Hatteras to Georges Bank, but recent decades of warming bottom water temperatures have caused the surfclam to shift its range to cooler waters north and offshore within the range of the ocean quahog, Arctica islandica. An ecotone now exists over much of the offshore range of the surfclam in which surfclams and ocean quahogs co-occur. Regulations prohibit fishers from landing both species in the same catch, limiting fishing to locations where the target species can be sorted …


Potential Repercussions Of Offshore Wind Energy Development In The Northeast United States For The Atlantic Surfclam Survey And Population Assessment, Sarah Borsetti, Daphne M. Munroe, Andrew M. Scheld, Eric N. Powell, John M. Klinck, Eileen E. Hofmann Feb 2023

Potential Repercussions Of Offshore Wind Energy Development In The Northeast United States For The Atlantic Surfclam Survey And Population Assessment, Sarah Borsetti, Daphne M. Munroe, Andrew M. Scheld, Eric N. Powell, John M. Klinck, Eileen E. Hofmann

Faculty Publications

The Atlantic surfclam Spisula solidissima fishery, which spans the U.S. Northeast continental shelf, is among the most exposed to offshore wind energy development impacts because of the overlap of fishing grounds with wind energy lease areas, the hydraulic dredges used by the fishing vessels, and the location of vessel home ports relative to the fishing grounds. The Atlantic surfclam federal assessment survey is conducted using a commercial fishing vessel in locations that overlap with the offshore wind energy development. Once wind energy turbines, cables, and scour protection are installed, survey operations within wind energy lease areas may be curtailed or …


Hide And Seek: An Exploration Of Antipredator And Predator Avoidance Mechanisms In Orthopodomyia Signifera In Response To Predation From Toxorhynchites Rutilus, Nathaniel Dahlberg Jan 2023

Hide And Seek: An Exploration Of Antipredator And Predator Avoidance Mechanisms In Orthopodomyia Signifera In Response To Predation From Toxorhynchites Rutilus, Nathaniel Dahlberg

Master's Theses

There have been many observations of larval Orthopodomyia signifera coexisting with the predator Toxorhynchites rutilus. There are three hypotheses that could explain how Or. signifera resists predation from Tx. rutilus. The first hypothesis states that larvae adapt behavioral changes that limit predation. The second hypothesis states thoracic setae serve as a physical defense that prevents Tx. rutilus from grasping Or. signifera. The third hypothesis states Or. signifera possess a chemical defense indicated by aposematic coloration. To test the first hypothesis larval Or. signifera were exposed to conspecific and heterospecific predation cues and their behavior was observed. Both cues …


A Preliminary Assessment Of The Spawning Potential Ratio Of Five Target Species Of The Coastal Gillnet Fishery In Guyana And Suriname, Tomas Willems, Elford Liverpool, Michael Hiwat Jan 2023

A Preliminary Assessment Of The Spawning Potential Ratio Of Five Target Species Of The Coastal Gillnet Fishery In Guyana And Suriname, Tomas Willems, Elford Liverpool, Michael Hiwat

Gulf and Caribbean Research

Data—limited stock assessment methods have the potential to positively impact livelihoods of fishermen around the world by providing management recommendations that aim to optimize sustainable yields from fisheries. Some years ago, a novel length— based (LB) method was developed for the assessment of spawning potential ratio (SPR), a measure of the reproductive capacity of fish stocks. We applied the LB—SPR method to 5 important target species of the coastal gillnet fishery in Guyana and Suriname. Nebris microps (Smalleye Croaker; 32% SPR) and Macrodon ancylodon (King Weakfish; 34% SPR) had the highest spawning potential, but remained below the 40% target level …


Is Temperature, Dissolved Oxygen, Or Salinity Driving Oyster Mortality On Breakwaters?, Ashten Notz, Aaron Bland, Ronald Baker Jan 2023

Is Temperature, Dissolved Oxygen, Or Salinity Driving Oyster Mortality On Breakwaters?, Ashten Notz, Aaron Bland, Ronald Baker

Gulf and Caribbean Research

No abstract provided.


Reflections On A Career Unplanned, Robert A. Glazer Jan 2023

Reflections On A Career Unplanned, Robert A. Glazer

Gulf and Caribbean Research

Sometimes life takes unexpected turns. I never planned to be a marine biologist; yet, after a long and unpredictable journey, that’s exactly where I found myself. After obtaining my B.S. in Fishery Biology from Colorado State University, I found myself meandering from job to job like a golden retriever following some vague scent. At first, I was hired by the Wyoming Game and Fish Department to work seasonally in Grand Teton National Park on the freshwater trout fisheries. Soon thereafter, I found myself cultivating oysters, clams, and other shellfish in California. The skills I developed there as an algologist led …


The Reproductive Biology Of Small Fishes And The Clutch Concept: Combining Macroscopic And Histological Approaches, David C. Heins, Nancy J. Brown-Peterson May 2022

The Reproductive Biology Of Small Fishes And The Clutch Concept: Combining Macroscopic And Histological Approaches, David C. Heins, Nancy J. Brown-Peterson

Faculty Publications

Accurate estimates of reproductive parameters important in understanding life history evolution and conservation of small fishes are dependent upon careful assignment of ovarian phases. Proper assignment is based upon the stages of propagule (oocyte) development, oocyte maturation and the location of any clutch or portion thereof within the ovaries. Macroscopic inspection and assignment of ovarian developmental phases have often been used for small freshwater fishes. By contrast, histological methods for assignment of reproductive phases have been developed and are widely used for marine fishes, but they have rarely been used for small freshwater fishes. We review oocyte development, ovum maturation, …


Investigation Of Dna Variability And Phylogenetic Relationships Of Perlesta (Plecoptera: Perlidae) In Mississippi, James C. Valentine, Mac H. Alford May 2022

Investigation Of Dna Variability And Phylogenetic Relationships Of Perlesta (Plecoptera: Perlidae) In Mississippi, James C. Valentine, Mac H. Alford

Master's Theses

The genus Perlesta Banks, 1906 (Plecoptera: Perlidae) consists of 35 species, 33 native to the United States and Canada and two native to China. For over a century these small, brown stonefly adults and freckled yellow nymphs have gone by the name of the type species of the genus, Perlesta placida, but taxonomic work in the genus since 1989 has resulted in the recognition of additional species. These species were mostly recognized and described using morphological characteristics, but two areas that are lacking include (1) linking nymphs to adults and (2) phylogenetic analysis of all species occurring in Mississippi …


Sensitivity Of A Lamp Assay For Detection Of The Dinoflagellate Amyloodinium Ocellatum In Simulated Field Conditions And Freeze Tolerance Of The Parasite, Robert Gonzales Apr 2022

Sensitivity Of A Lamp Assay For Detection Of The Dinoflagellate Amyloodinium Ocellatum In Simulated Field Conditions And Freeze Tolerance Of The Parasite, Robert Gonzales

Master's Theses

The obligate parasitic dinoflagellate Amyloodinium ocellatum causes amyloodiniosis in warm water marine fishes. The prolific parasite, which has a direct, three-stage life cycle, is highly infectious and can cause heavy losses in aquaculture. Prevention, biosecurity, and early detection are vital for control. In this work, microscopy and a loop-mediated isothermal amplification (LAMP) assay were compared for early diagnosis of A. ocellatum in cultured stocks, and the freeze tolerance of tomonts was assessed to determine if frozen wild fish used as fish food can serve as a potential vector for the parasite.

The lowest dinospore concentration that could be detected by …


Life History Of Swordfish, Xiphias Gladius, Caught In The Northern Gulf Of Mexico, Anna K. Millender, Jeremy M. Higgs, Nancy J. Brown-Peterson, Michael J. Andres, James S. Franks Jan 2022

Life History Of Swordfish, Xiphias Gladius, Caught In The Northern Gulf Of Mexico, Anna K. Millender, Jeremy M. Higgs, Nancy J. Brown-Peterson, Michael J. Andres, James S. Franks

Gulf and Caribbean Research

The current study examined 93 Swordfish, Xiphias gladius, (64 females, 27 males, 2 unknown) ranging in size from 77.6–246.3 cm lower jaw fork length (LJFL) from the northern Gulf of Mexico (GOM). Samples were collected between March and August in 2005–2007, 2017–2019 and 2021. Age estimates of 51 Swordfish resulted in a maximum observed age of 11 years (205.0 cm LJFL) and 7 years (190.4 cm LJFL) for females and males, respectively. Observed and back—calculated length—at—age data were fitted to 4 growth models (2— and 3— parameter von Bertalanffy, Gompertz, and logistic). The 2—parameter von Bertalanffy was the model …


Kinorhynch Diversity In The Southern Gulf Of Mexico And A Description Of Dracoderes Chaac Sp. Nov., Stephen C. Landers, Kellan Hoffman, Nuria Sanchez, Martin Sorensen Jan 2022

Kinorhynch Diversity In The Southern Gulf Of Mexico And A Description Of Dracoderes Chaac Sp. Nov., Stephen C. Landers, Kellan Hoffman, Nuria Sanchez, Martin Sorensen

Gulf and Caribbean Research

Sediment collections from the southern Gulf of Mexico between the Texas—Mexico border and the Yucatán Peninsula have resulted in many new kinorhynch species distribution records and the finding and taxonomic description of a new species, Dracoderes chaac sp. nov. This study focused on the non—echinoderid members of the Phylum Kinorhyncha, many of which are rare or restricted to only a few locations. A total of 136 specimens were identified from 24 sediment stations, distributed among the following species: Antygomonas gwenae, Campyloderes vanhoeffeni, Centroderes readae, Condyloderes flosfimbriatus, Co. rohalorum, Cristaphyes panamensis, Dracoderes chaac sp. nov., …


First Data On Aquaculture Of The Tripletail, Lobotes Surinamensis, A Promising Candidate Species For U.S. Marine Aquaculture, Eric Saillant, Nicholas Adams, Jason T. Lemus, James S. Franks, Yonathan Zohar, John Stubblefield, Christopher Manley Jun 2021

First Data On Aquaculture Of The Tripletail, Lobotes Surinamensis, A Promising Candidate Species For U.S. Marine Aquaculture, Eric Saillant, Nicholas Adams, Jason T. Lemus, James S. Franks, Yonathan Zohar, John Stubblefield, Christopher Manley

Faculty Publications

The Tripletail, Lobotes surinamensis, is a warm-water pelagic fish that is increasingly targeted by U.S. anglers. The superior quality of Tripletail flesh coupled with the lack of domestic commercial fisheries stimulated interests to develop aquaculture of this species. In this work, photo-thermal conditioning of captive-held broodstocks promoted maturation in females, but spontaneous spawning was not observed. GnRHa slow-release implants induced ovulation in late vitellogenic females but fertility remained below 10% when GnRHa was administered alone. However, spawns with high fertility (up to 85%) were obtained when a dopamine antagonist was administered in conjunction with GnRHa implants indicating dopamine inhibition …


The Status Of Spotted Seatrout (Cynoscion Nebulosus) As A Technologically Feasible Species For U.S. Marine Aquaculture, Reginald Blaylock, Eric Saillant, Angelos Apeitos, David Abrego, Paul Cason, Robert Vega Jun 2021

The Status Of Spotted Seatrout (Cynoscion Nebulosus) As A Technologically Feasible Species For U.S. Marine Aquaculture, Reginald Blaylock, Eric Saillant, Angelos Apeitos, David Abrego, Paul Cason, Robert Vega

Faculty Publications

Culture models and facilities for large-scale, commercial production of popular Gulf of Mexico species are unavailable. The spotted seatrout (Cynoscion nebulosus) is one of the most popular recreational fishes in the Gulf of Mexico. Seatrout culture techniques were adapted from red drum (Sciaenops ocellatus) protocols developed in the 1970s. Broodstock husbandry, spawning, and extensive pond rearing techniques using fertilized and bloomed brackish ponds were well-established by the 1980s. By 2018, approximately 80 million 25–30-day old seatrout had been produced, mainly for stock enhancement. Cannibalism and poor nutrition hindered intensive tank culture. Between 2005 and 2015, an …


Vertebrates At The University Of Southern Mississippi: A Wildlife Survey Of The Bear Point Bayou And Surrounding Gulf Park Campus, Hannah Mcduffie May 2021

Vertebrates At The University Of Southern Mississippi: A Wildlife Survey Of The Bear Point Bayou And Surrounding Gulf Park Campus, Hannah Mcduffie

Honors Theses

This project originated through interest in pursuing a field-based research project involving vertebrates. After conducting literature reviews, it was found that the Bear Point Bayou running through the University of Southern Mississippi Gulf Park Campus has never been thoroughly surveyed for species richness (Mohrman et al. 2016). Four sites on the Gulf Park Campus were chosen and vertebrate species were documented and identified through observations, camera trapping, and vocalization recordings. These data, along with species previously recorded on campus, were combined, and compared to data from the Gulf Coast Phenology Trail of which the Gulf Park Campus was recently added …


Trophic Ecology Of Mesopelagic Fish Larvae And Juveniles In The Northern Gulf Of Mexico, Emily Gipson May 2021

Trophic Ecology Of Mesopelagic Fish Larvae And Juveniles In The Northern Gulf Of Mexico, Emily Gipson

Master's Theses

The deep-pelagic environment encompasses ocean waters below 200 m depth, and comprises 90% of the volume of the Gulf of Mexico. Deep-pelagic fishes are important prey for many oceanic consumers, but relatively little is known about their early life history, including larval fish trophic ecology. An understanding of the role deep-pelagic fish larvae have in oceanic food webs is important in the development of ecosystem models that examine the connectivity (via vertical migrations) between the deep-pelagic and epipelagic environments with respect to trophic interactions, nutrient cycling, and carbon sequestration. In this study, archived plankton samples collected during 2010 and 2011 …


Fishing For Food: Values And Benefits Associated With Coastal Infrastructure, Cassandra M. Nieman, Alexie N. Rudman, Margaret L. Chory, Grant D. Murray, Luke Fairbanks, Lisa M. Campbell Apr 2021

Fishing For Food: Values And Benefits Associated With Coastal Infrastructure, Cassandra M. Nieman, Alexie N. Rudman, Margaret L. Chory, Grant D. Murray, Luke Fairbanks, Lisa M. Campbell

Faculty Publications

While there is substantial literature about the socio-cultural characteristics and values associated with recreational and commercial fisheries in the U.S., studies directed at those who ‘fish for food’—those who depend on consuming their catch to various degrees—are relatively sparse. Using qualitative data collected through 80 semi-structured interviews with fishers in the summer and fall of 2018 in Carteret County, North Carolina, this study aims to better understand the group of recreational fishers who consume their catch by describing social and cultural dimensions and values associated with fishing for food, examining the role of infrastructure in facilitating access to benefits associated …


A Sea Turtle Population Assessment For Florida's Big Bend, Northeastern Gulf Of Mexico, Ryan M. Chabot, Ryan C. Welsh, Cody R. Mott, Jeffrey R. Guertin, Brian M. Shamblin, Blair E. Witherington Jan 2021

A Sea Turtle Population Assessment For Florida's Big Bend, Northeastern Gulf Of Mexico, Ryan M. Chabot, Ryan C. Welsh, Cody R. Mott, Jeffrey R. Guertin, Brian M. Shamblin, Blair E. Witherington

Gulf and Caribbean Research

Coastal waters of Florida’s Big Bend, Gulf of Mexico (GOM) once supported one of the largest sea turtle fisheries in the United States. To fill an information gap in this region on abundance and distribution of sea turtles, we used vessel—based distance sampling and active capture methods to characterize current foraging aggregations near the St. Martins Marsh Aquatic Preserve. Over 10 sampling periods between 2012—2018, we completed 513 km of transects and recorded 819 turtles among 4 species—green turtle (Chelonia mydas, n = 624), Kemp’s ridley (Lepidochelys kempii, n = 147), loggerhead (Caretta caretta, …


Progress On Research Regarding Ecology And Biodiversity Of Coastal Fisheries And Nektonic Species And Their Habitats Within Coastal Landscapes, Mark S. Peterson, Michael J. Andres Jan 2021

Progress On Research Regarding Ecology And Biodiversity Of Coastal Fisheries And Nektonic Species And Their Habitats Within Coastal Landscapes, Mark S. Peterson, Michael J. Andres

Faculty Publications

This paper aims to highlight the new research and significant advances in our understanding of links between coastal habitat quality/quantity/diversity and the diversity of fisheries species and other mobile aquatic species (hereafter nekton) that use them within coastal landscapes. This topic is quite diverse owing to the myriad of habitat types found in coastal marine waters and the va-riety of life history strategies fisheries species and nekton use in these environments. Thus, we focus our mini-review on five selective but relevant topics, habitat templates, essential fish habitat, habitat mosaics/habitat connectivity, transitory/ephemeral habitat, and the emerging/maturing approaches to the study of …


Determining The Trophic Role Of Red Snapper (Lutjanus Campechanus) In Mississippi State Waters Using Stomach Content And Stable Isotope Analysis, Branden Kohler Dec 2020

Determining The Trophic Role Of Red Snapper (Lutjanus Campechanus) In Mississippi State Waters Using Stomach Content And Stable Isotope Analysis, Branden Kohler

Master's Theses

The goal of this study was to determine the diet composition, trophic position and ecological role of red snapper (Lutjanus campechanus) in Mississippi state waters utilizing stable isotopes (δ13C and δ15N) and stomach content analysis. Stable isotope analysis of fish and their prey can provide information on species-specific basal resource utilization, diet composition and trophic position which can improve food web models and inform fisheries management decisions. Particulate organic matter (POM), the presumed base of the food web, red snapper muscle tissue, and red snapper stomach contents were collected from 25 sites in 2016 and …


Microplastic Abundance, Distribution And Impacts On Sargassum-Associated Juvenile Fishes In The Gulf Of Mexico, Olivia Lestrade Dec 2020

Microplastic Abundance, Distribution And Impacts On Sargassum-Associated Juvenile Fishes In The Gulf Of Mexico, Olivia Lestrade

Master's Theses

Microplastics are a concern in marine environments because they are highly durable, ubiquitous, and can be mistaken for food and ingested by small organisms. Pelagic Sargassum, an important habitat for larval and juvenile stages of many fish species, is found in large surface aggregations, and may provide complex structure in which microplastics become trapped. This could lead to greater risk of microplastic ingestion by fish early life stages associated with Sargassum habitats. To better understand the impacts of microplastics within Sargassum communities, this study examined 1) microplastic concentrations and ingestion by juvenile fishes associated with Sargassum; 2) the microbial …


Assessing The Nursery-Role Function Of Pelagic Sargassum For Juvenile Fishes In The Northern Gulf Of Mexico, Courtney Stachowiak Dec 2020

Assessing The Nursery-Role Function Of Pelagic Sargassum For Juvenile Fishes In The Northern Gulf Of Mexico, Courtney Stachowiak

Master's Theses

Sargassum, a genus of holopelagic brown algae, floats at the ocean’s surface using air-filled bladders and forms a complex comprised of two species, S. natans and S. fluitans. Oceanic processes (e.g., Langmuir circulation, etc.) aggregate Sargassum into mats and weedlines, and primarily distribute the algal complex throughout the North Atlantic Ocean and the Gulf of Mexico (GOM). These floating habitats provide shelter and feeding opportunities for a diverse community of invertebrates and fishes. Sargassum is a presumed nursery habitat for juvenile stages of commercially- and recreationally-targeted fishery species. In this study, I estimated the standardized abundances of juvenile …


The "Challenge" Of Depletion: Why The Oyster Fishery Is Not Self-Regulating, Eric N. Powell, John M. Klinck, Leanne M. Poussard Aug 2020

The "Challenge" Of Depletion: Why The Oyster Fishery Is Not Self-Regulating, Eric N. Powell, John M. Klinck, Leanne M. Poussard

Faculty Publications

© 2020 National Shellfisheries Association. All rights reserved. The possibility that the economics of the oyster fishery impose a self-limitation on overharvesting has been proffered on occasion. The inefficiency of harvesting by the fishery has been evaluated and estimates of the exploitation rate permissible under conditions of maximum sustainable yield have been obtained in previous studies. The question becomes to what extent does the inefficiency of harvest interact with the economics of the fishery to compromise ready detection of overfishing? This study explores the possibility that the constraint of economics on the fishery occurs at oyster exploitation rates that are …


Interrelationships Among Monorchiid Trematodes With Special Emphasis On Some Northwestern Atlantic Genera, Apryle Panyi Aug 2020

Interrelationships Among Monorchiid Trematodes With Special Emphasis On Some Northwestern Atlantic Genera, Apryle Panyi

Master's Theses

The Monorchiidae Odhner, 1911 is a cosmopolitan family of flukes (Trematoda: Digenea) comprising species that parasitize the digestive tract of estuarine and marine fishes as adults. Compared with other oceans, recent morphological or molecular taxonomic work conducted on monorchiid species from the northwestern Atlantic Ocean has been sparse (Manter, 1931; Overstreet, 1969; Andres et al., 2018; Wee et al., 2018, 2019, 2020). Therefore, the present work investigated the interrelationships of some monorchiids from the northwestern Atlantic Ocean with emphasis on several genera and investigated if Lasiotocus minutus (Manter, 1931) Thomas, 1959 constitutes a complex of cryptic species. New morphological and …


Regional Differences In Wild North American River Otter (Lontra Canadensis) Behavior And Communication, Sarah Walkley May 2020

Regional Differences In Wild North American River Otter (Lontra Canadensis) Behavior And Communication, Sarah Walkley

Dissertations

This study focuses on the vocalization repertoires of wild North American river otters (Lontra canadensis) in New York and California. Although they are the same species, these two established populations of river otters are separated by a significant distance and are distinct from one another. River otters are semi-aquatic social predators that can be found throughout North America. This is the first study to examine the vocalizations of wild river otters, and results are compared across field sites in the different regions. River otter vocalizations and behaviors in New York were recorded using Bushnell Aggressor trail cameras that …


Maturation Spawning And Larviculture Of Atlantic Croaker (Micropogonias Undulatus) At Low Salinity, Edithrose Fairweather May 2020

Maturation Spawning And Larviculture Of Atlantic Croaker (Micropogonias Undulatus) At Low Salinity, Edithrose Fairweather

Master's Theses

Atlantic Croaker is a popular baitfish among anglers targeting a variety of gamefish in the Gulf of Mexico. Aquaculture of this species could help meet the demand for Croaker, especially during winter when wild-caught Croaker are unavailable. Currently, Croaker aquaculture involves broodstock maturation, spawning, and larval culture at high salinity. This protocol prevents the direct use of coastal water for culture along the Mississippi Gulf coast where salinity is low. This study examined the feasibility of performing hatchery production of Atlantic Croaker at low salinity.

Culture of Croaker broodstock at 10, 20, and 30 psu during the maturation period was …


An Analysis Of Dredge Efficiency For Surfclam And Ocean Quahog Commercial Dredges, Leanne Poussard May 2020

An Analysis Of Dredge Efficiency For Surfclam And Ocean Quahog Commercial Dredges, Leanne Poussard

Master's Theses

Between 1997 and 2011, The National Marine Fisheries Service conducted 50 depletion experiments to estimate survey gear efficiency and stock density for Atlantic surfclam (Spisula solidissima) and ocean quahog (Arctica islandica) populations using commercial hydraulic dredges. The Patch Model was formulated to estimate gear efficiency and organism density from the data. The range of efficiencies estimated is substantial, leading to uncertainty in the application of these estimates in stock assessment. Analysis of depletion experiment simulations showed that uncertainty in the estimates of gear efficiency from depletion experiments was reduced by higher numbers of dredge tows per experiment, more tow overlap …


Abundance And Occurrence Of Common Bottlenose Dolphins (Tursiops Truncatus) In Three Estuaries Of The Northwestern Gulf Of Mexico, Errol Ronje, Heidi Whitehead, Kevin Barry, Sarah Piwetz, Juliane Struve, Vincent Lecours, Lance Garrison, Randall S. Wells, Keith D. Mullin Jan 2020

Abundance And Occurrence Of Common Bottlenose Dolphins (Tursiops Truncatus) In Three Estuaries Of The Northwestern Gulf Of Mexico, Errol Ronje, Heidi Whitehead, Kevin Barry, Sarah Piwetz, Juliane Struve, Vincent Lecours, Lance Garrison, Randall S. Wells, Keith D. Mullin

Gulf and Caribbean Research

Current abundance estimates for populations of common bottlenose dolphins (Tursiops truncatus, Montagu, 1821) in bays, sounds, and estuaries are lacking throughout most of the northwestern Gulf of Mexico, including areas of Texas and western Louisiana. To address this issue, we conducted 92 small-boat photographic identification surveys covering ~2000 km2 and comprising ~11,000 km of track-line in winter and summer seasons in West Bay, TX (2014 – 2015, n = 25), the Galveston Bay, TX system (2016, n = 50), Sabine Lake, TX (2017, n = 17), and adjacent coastal waters. Individual dolphin encounter histories were constrained by …