Animal Sciences Commons^™

Blue Crab Reproductive Output And Phenology In A Changing Climate, Blaise Rohan

Master's Theses

Globally, ecosystems are experiencing rising temperatures due to climate change, with potential consequences for reproductive investment and timing in many species. Blue crabs, Callinectes sapidus, support valuable commercial fisheries throughout the U.S. Atlantic and Gulf coasts, and understanding variation in reproductive output has important management and conservation implications. This study examined two components of blue crab reproduction: (1) reproductive investment across populations spanning multiple latitudes (New York, New Jersey, North Carolina, Mississippi, and Texas), using a space-for-time substitution to assess the effects of varying thermal regimes on fecundity and egg quality, and (2) spawning phenology in North Carolina from …

Vegetation Species And Bed Position May Drive Epifaunal But Not Nekton Habitat Use In Estuarine Submerged Vegetation In The Mobile-Tensaw River Delta, Alabama, Steven Vroljik, Kathryn O'Shaughnessy, Ashley Mcdonald, Zoey Hendrickson, Bethany Kiley, Anna Reimer, Sierra Robertson, Samantha Smith, Edward Sullivan, Charles Martin

Gulf and Caribbean Research

Submerged aquatic vegetation (SAV) supports nekton and epifaunal macroinvertebrates, sustaining food webs and ecosystem services in estuaries. Invasive SAV can alter these dynamics by displacing native vegetation and restructuring communities. In Alabama’s Mobile-Tensaw Delta (MTD), Eurasian milfoil (Myriophyllum spicatum) is rapidly expanding and outcompeting native wild celery (Vallisneria americana). This study compared nekton and epifaunal assemblages between M. spicatum and V. americana, focusing on edge versus interior positions. Nekton surveys identified 22 taxa (M. spicatum, n = 13; V. americana, n = 18), but assemblages did not differ significantly between vegetation types …

Characterization Of A Coastwide Sheepshead (Archosargus Probatocephalus) Fishery Reveals Increased Fishing Pressure During Spawning Activity In Texas, Ethan T. Getz, Catherine M. Eckert, Charles Downey Iii

Gulf and Caribbean Research

Sheepshead (Archosargus probatocephalus) have been characterized as one of the most vulnerable species to overfishing in the Gulf of Mexico (GOM) based on their reproductive strategy of spawning in aggregations. Here, we analyzed fishery—independent and dependent data (1983—2023) collected by the Texas Parks and Wildlife Department to assess Sheepshead populations and describe the fishery in Texas. Gill net sampling was used to describe Sheepshead abundance and distribution, while creel survey data and commercial landings were used to determine spatial and temporal characteristics of the fishery and evaluate targeted fishing activity during the spawning season. Sheepshead encountered in gill …

Oyster Drill (Stramonita Haemastoma Complex) Habitat Preferences In A Shallow Coastal Estuary, Coen Mcgarrah, Cynthia Lupton, Eric Sparks, Jennifer L. Debose

Gulf and Caribbean Research

Southern oyster drill snails (Stramonita haemastoma complex) are nuisance organisms within the Gulf of Mexico. This is due to their damaging impact on recovering and farmed oyster (Crassostrea virginica) populations, which are one of the drills’ main food sources. Oyster reef recovery and increased aquaculture production are priorities for Mississippi and the wider northern Gulf coast. The Grand Bay National Estuarine Research Reserve (NERR) hosts multiple oyster reef restoration sites within its boundaries, yet no comprehensive survey of oyster drill abundance has been conducted in this area to date. Additionally, knowledge of oyster drill preferences for sediment …

First Photo-Identification Resighting Of A Male Sperm Whale (Physeter Macrocephalus) Between Guadeloupe, Lesser Antilles And Andøya, Northern Norway, Rocío Prieto González, Lisa Steiner, Zoë Morange, Tiu Similä, Marten Brill, Cédric Millon, Laurent Bouveret

Gulf and Caribbean Research

No abstract provided.

Notes On The Ichthyofauna Associated With Artisanal Fishing In A Severely Impacted Estuary In The Southwestern Gulf Of Mexico During The Rainy Season, Rodrigo Vivanco-Cadena, César Meiners-Mandujano, Roberto Martín Cruz-Castán

Gulf and Caribbean Research

No abstract provided.

Manatee Dock Sign Distribution And Its Influence On Publicly-Sourced Sighting Reports In Alabama, Daniela Payán Arias, Sophia C. Corde, Ruth H. Carmichael

Gulf and Caribbean Research

No abstract provided.

Life History And Distribution Of Two Species Of Cownose Ray, Rhinoptera Bonasus And Rhinoptera Brasiliensis, In Mississippi Coastal Waters, Anna Millender

Master's Theses

Historically, the American Cownose Ray (Rhinoptera bonasus) was considered the only rhinopterid residing in the northern Gulf of Mexico (GOM); however, recent studies have confirmed the presence of the Brazilian Cownose Ray (Rhinoptera brasiliensis) throughout this region. The current study investigated the life history and distribution of both species within Mississippi waters, an area that previously represented a data gap for both species. From April 2016 – July 2025, 193 R. bonasus and 94 R. brasiliensis were analyzed to describe the reproductive biology. Reproductive timing, mating, gestation length, and parturition were similar among species. Although more …

Sibship Analysis Of Fall And Spring Spawn Gulf Sturgeon Eggs In The Choctawhatchee River, Florida, Lyric Mccullouch

Honors Theses

The Gulf sturgeon (Acipenser oxyrinchus desotoi) is an anadromous species that inhabits rivers along the northern Gulf of Mexico. Facing challenges from overfishing and habitat alteration, the Gulf sturgeon is listed as threatened under the Endangered Species Act. This study investigated the genetic distinctiveness of fall and spring spawning groups of Gulf sturgeon in the Choctawhatchee River, a critical habitat for the species. In this study, I used microsatellite loci to analyze Gulf sturgeon eggs previously collected in the fall and spring of 2019 and 2020. The goals of this study were to verify the genetic identity of …

Lack Of Consistent Diurnal Trends In Acoustic Metrics From Restored Coral Reefs, Jeremy Velázquez-Alvarado, Valentina Pérez-García, Javier S. Tellechea, Joni T. Backstrom, Alex Mercado-Molina

Gulf and Caribbean Research

Once vibrant ecosystems, coral reefs are degrading at unprecedented rates due to natural and human—induced disturbances, necessitating immediate restoration and conservation efforts. Evaluating the success of these projects often involves assessing changes in reef biodiversity. Bioacoustics has emerged as a promising, non—invasive method for such evaluations, though its efficacy remains debated. This study aimed to determine whether the diurnal soundscapes of restored coral reefs are consistent across different time frames (months) and spatial scales (reefs), which is crucial for developing reliable monitoring tools for reef health. To achieve this, 2 commonly used acoustic indices, the Acoustic Complexity Index (ACI) and …

Mercury Concentrations, Health, And Marine Food Consumption Across Four Eastern Caribbean Populations: Insights From A Novel Community-Based Study, Russell Fielding, Catherine Brown, Jessica Dutton, Martin S. Forde, Heather Harewood, Lisa Hunt, Catherine Macdonald, Cameron Mewhirter, Vincent Reid, Madison Smith, Holly Taylor, Katelyn Zimmerman

Gulf and Caribbean Research

Mercury (Hg), as an environmental pollutant, can have harmful effects on human health. A common way that people are exposed to Hg is through seafood consumption. This project was designed to investigate Hg exposure through seafood consumption and its health effects among adults in 4 Caribbean countries: Barbados (n = 117), Grenada (n = 90), St. Lucia (n = 126), and St. Vincent & the Grenadines (n = 77). We applied a novel, community—based method, which involved recruiting and paying local barbers and hairstylists to collect hair samples from their clients who consented to join the project as participants. Participants …

New Observations Of Common Snook, Centropomus Undecimalis, In Mississippi Coastal Waters, With A Summary Of Local Records, Tiffany A. Weidner, William C. Tilley, Brooke Doucet, Angelos Apeitos, Eric A. Saillant, James S. Franks, Jeremy M. Higgs

Gulf and Caribbean Research

No abstract provided.

Investigating Nekton Response To Changing Salinities In The Mississippi Sound: An Experimental And Statistical Approach, Adam Murray

Master's Theses

The Mississippi Sound provides nursery habitats for many coastal species and is recognized for its commercial fisheries. Previous freshening events linked to the Bonnet Carré Spillway, a Mississippi River flood diversion structure, proved catastrophic for oyster populations in the Mississippi Sound, but effects on mobile fish and shellfish species are not well-defined. The planned Mid-Breton Sediment Diversion (MBSD), an initiative to combat wetland loss, is also forecasted to lower salinities in the region, increasing the need to better understand responses of commercially and ecologically important species to freshening events. The objective of this study was to characterize effects of salinity …

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 …

A Preliminary Investigation Of Adherence To Shell Length Regulations And Adaptive Capacity Of The Turneffe Atoll Queen Conch (Aliger Gigas) Fishery, Belize, Elsa M. K. Brenner, Vincent Sollitto, Vincent Baribeau, Rebecca Branconi, Paul Simonin

Gulf and Caribbean Research

No abstract provided.

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 …

Genetic Parameters For Heat And Salinity Stress Tolerance In Northern Gulf Of Mexico Eastern Oyster, Crassostrea Virginica, Paul Mcdonald

Master's Theses

Summer mortalities in Gulf of Mexico eastern oysters have been linked to excessively high temperatures, and chronic exposure to low salinity. In this study, the feasibility of improving tolerance to these two stresses by selection was evaluated in common garden experiments employing a pool of 160 families. Heat stress tolerance was evaluated in seed (3.5 months) and adults (14 months) by applying a sustained temperature of 38-39 °C until all oysters expired. Low salinity challenges on juveniles (9 months) and adults (15 months) applied a salinity of 2.5 psu. Survival duration of individual oysters during challenges was recorded and tissue …

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

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

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 …

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 …

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 …

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 …

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

Gulf and Caribbean Research

No abstract provided.

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

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

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 …

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., …

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 …

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 …