Marine Biology Commons^™

The Distribution, Composition, And Management Of Drifting Fish Aggregating Devices (Dfads) In The North Atlantic Ocean, Erin E. Kimak

All HCAS Student Capstones, Theses, and Dissertations

Drifting Fish Aggregating Devices (dFADs) are a gear accessory utilized on a global scale by commercial fishers to increase catch size and efficiency of target pelagic fishes such as tuna and dolphinfish. Despite their widespread use, there are few scientific estimates of the total number of abandoned or beached dFADs in the Atlantic Ocean and Caribbean Basin or the compliance of dFAD use with t-RFMO recommendations. Previous studies have utilized the modeled drift trajectories of dFADs to predict beaching probability and location, but this study is the first of its kind, analyzing true beaching events. This study identifies the beaching …

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 …

Effects Of Tropical Cyclones On Incubation And Hatch Frequency Of Marine Turtles In Broward County, Fl: An Exploratory Look For Potential Cues Of Environmentally Cued Hatching (Ech), Alexis Peterson

All HCAS Student Capstones, Theses, and Dissertations

Due to climate change and warming sea surface temperatures (SST), the intensity and frequency of tropical cyclones in the North Atlantic are continuing to increase. Tropical cyclones have many direct and indirect effects on coastal and marine species, such as sea turtles. Sea turtles are extremely vulnerable to climate change, due to having life history, physiology, and behavioral traits that are heavily influenced by environmental factors (Fuentes and Porter 2013). This study examined whether tropical cyclones serve as a triggering event for environmentally cued hatching (ECH) in loggerhead (Caretta caretta) and green (Chelonia mydas) turtle nests …

Optimization Of Grow-Out Of Bouldering Coral Microfragments: Land Vs. Offshore Nursery, Ashlee A. Steinberg

All HCAS Student Capstones, Theses, and Dissertations

Corals along the Florida Reef Tract and the wider Caribbean have been declining for decades. Low densities of adult colonies hinder the ability of corals to replenish themselves through sexual reproduction, thus reef managers are focusing on restoration actions that increase coral biomass. Microfragmentation is a way to quickly increase the biomass of bouldering corals by cutting the coral into small pieces which forces the coral to allocate its resources away from reproduction and back into growth, increasing its growth rate. This study assessed the optimal location for grow-out (land vs. offshore nursery) and its synergy with size of fragment …

Journey Into Midnight: Population Dynamics, Vertical Distribution, And Trophic Ecology Of Whalefishes (Cetomimidae) In The Bathypelagic Gulf Of Mexico, Rachel Eckley

All HCAS Student Capstones, Theses, and Dissertations

Despite comprising the largest biome on Earth, the bathypelagic zone inhabitants represent a “black hole” in the understanding of deep-oceanic functioning due to physical and monetary limitations. The characteristics of the global bathypelagic realm create a limiting environment only inhabitable by specially adapted fauna. These include whalefishes (Stephanoberycoidei: Cetomimidae), which are a taxonomically and systematically challenging group of primarily bathypelagic fishes.

Cetomimids were collected in the Gulf of Mexico using high-speed rope trawls and a multiple-opening-and-closing net system. Population dynamics were described using morphometric analysis. Vertical distributions, including diel variation, were described using a modified boxplot of abundance standardized by …

Trophic Ecology And Functional Morphology Of The Scaleless Black Dragonfishes (Family Stomiidae; Subfamily Melanostomiinae), Ryan P. Mcgonagle

All HCAS Student Capstones, Theses, and Dissertations

Dragonfishes (Family Stomiidae) are considered the most numerically important and diverse taxon of higher-level meso- and bathypelagic predators in oceanic food webs, with the subfamily Melanostomiinae contributing 220 of the 317 species. The Stomiidae is also the most speciose fish family in the Gulf of Mexico. The relationship between diversity (both systematic and morphological) and feeding of the Melanostomiinae has not been previously examined due to sample size limitation. Here the diet and morphology of 16 species of dragonfishes in the Gulf of Mexico was examined to address the question, “Does the extraordinary speciation in this most-diverse deep-pelagic fish clade …

Assessment Of Monochloramine Toxicity On Three Small Coastal Organisms, Ashley K. Le

All HCAS Student Capstones, Theses, and Dissertations

Monochloramine ( is a secondary disinfectant used by water treatment facilities to eliminate lingering bacteria in basins, filters, and pipelines. While an effective disinfectant, monochloramine can have negative effects on aquatic organisms. Organis ms affected by the chemical can include species whose environment is near to effluent sites and aquaculture facilities that use tap water lines or has water intake pipes near to effluent sites. Three species commonly found in south Florida that are lik ely exposed to MCA by effluent sites or aquaculture facilities are mosquitofish Gambusia affinis pink shrimp Farfantepenaeus duorarum and the hard clam Mercenaria mercenaria These …

Ontogenetic Variation In Sciaenid Otolith Morphometry With Fish Size From The Northern Gulf Of Mexico, Thomas C. Ingalls

All HCAS Student Capstones, Theses, and Dissertations

Sciaenids are a diverse family of coastal fishes and their fisheries are an important industry in the United States. In the northern Gulf of Mexico this industry is dominated by six species, specifically, red drum (Sciaenops ocellatus), black drum (Pogonias cromis), spotted seatrout (Cynoscion nebulosus), sand seatrout (C. arenarius), Atlantic croaker (Micropogonias undulatus), and spot (Leiostomus xathurus). Sagittal otoliths of all species were evaluated for changes in size and shape in relation to changes in fish total length and age across a variety of seasons and habitats. Evaluation …

A Predator-Based Methodology For Studying Predator-Prey Relationships In Fishes, Ashley Vettese

All HCAS Student Capstones, Theses, and Dissertations

Changes in the ocean including acidification, increasing temperatures, loss of habitat, and increased hypoxic events has the potential to change predator-prey relationships. These changes in single interactions can then have effects on population sizes, community structures, and changes in trophic cascades. Understanding how changing abiotic factors impact predator-prey relationships will be crucial for understanding what populations and communities will look like under future ocean conditions. In this review, the goals are to (1) summarize the current knowledge on how changing ocean conditions affect predator-prey relationships; (2) describe an example predator-based approach to examine how changing these changing factors impact predator-prey …

Tunel Apoptotic Cell Detection In Stony Coral Tissue Loss Disease (Sctld): Evaluation Of Potential And Improvements, E. Murphy Mcdonald

All HCAS Student Capstones, Theses, and Dissertations

Stony coral tissue loss disease (SCTLD) is a highly lethal coral disease that has caused a dramatic loss of coral tissue along the Florida Reef Tract and throughout the Wider Caribbean. This study seeks to understand whether programmed cell death (apoptosis) is involved in the pathology of the highly virulent SCTLD tissue loss lesion. Tissues from diseased colonies of Pseudodiploria strigosa collected in 2018 and 2020 were stained using the terminal deoxyribonucleotidyltransferase (TdT) mediated dUTP-biotin nick end labeling (TUNEL) assay to visualize areas of programmed cell death. The archived tissue samples collected in 2018 exhibited a significantly higher degree of …

Investigation Of Sulfur Cycling In Marine Sponge Cinachyrella Spp. From A South Florida Reef, Shelby K. Cain

All HCAS Student Capstones, Theses, and Dissertations

Symbionts within marine sponges are actively participating in the biogeochemical cycles. Among them, the role of symbiont microbes in the sulfur cycle remains a mystery. This study measured the abundance of microbes within the genus Cinachyrella before and after exposure to hydrogen sulfide. A four-part study was conducted: a) five-hour drop experiments, b) vertical distribution experiments, c) five-hour uptake experiments, and d) long-term exposure experiments. The five-hour drop experiment utilized a microsensor to measure sulfide levels, which was lowered 1.0 mm every thirty minutes for a total of 5 hours. Three trials were performed, each with one sponge and a …

Life History, Biology, Fisheries, And Management For Six Lesser Known Species Of Hammerhead Sharks (Family: Sphyrnidae), Emma M. Brennan

All HCAS Student Capstones, Theses, and Dissertations

Historically, sharks were not considered to be of high commercial value due to low demand and modest catch rates in comparison to bony fishes. However, with recent heightened demand for shark products, their economic value has increased profoundly, which has led to overharvesting of many species. Sharks are considered as a K-selected species, which includes life history traits such as slow growth, late maturity, few offspring, and slow reproductive rates. Given the slow intrinsic rate of increased characteristic of most species of sharks, few species can support heavy fishing pressure and are vulnerable to drastic population declines as a result …

Functional Review And Macrostructure Of The Caecum In Ardeidae, Lola R. Mildren

All HCAS Student Capstones, Theses, and Dissertations

Situated on the lower digestive tract, caeca typically project cranially from the juncture of the small and large intestine. Recent studies have proposed that the role of caeca in the avian system is to act as fermentation chambers to synthesize vitamins, modulate gut microflora, and absorb nutrients; however, functionality differs with diet. Caeca are a typical characteristic of the avian gastrointestinal tract, with varying sizes and shapes, or even rudimentary or absent in some species. Caeca are notably singular and relatively small in Ardeids. Morphometric consistency in the number and presence of caeca on the lower intestinal tract of Ardeids …

Effects Of Surfactants On The Generation Of Sea Spray During Tropical Cyclones, Breanna L. Vanderplow

All HCAS Student Capstones, Theses, and Dissertations

Despite significant improvement in computational and observational capabilities, predicting intensity and intensification of major tropical cyclones remains a challenge. In 2017 Hurricane Maria intensified to a Category 5 storm within 24 hours, devastating Puerto Rico. In 2019 Hurricane Dorian, predicted to remain tropical storm, unexpectedly intensified into a Category 5 storm and destroyed the Bahamas. The official forecast and computer models were unable to predict rapid intensification of these storms. One possible reason for this is that key physics, including microscale processes at the air-sea interface, are poorly understood and parameterized in existing forecast models.

Under tropical cyclones, the air-sea …

Assessing The Potential For Range Expansion Of The Red Tide Algae Karenia Brevis, Edward W. Young

All HCAS Student Capstones, Theses, and Dissertations

Phytoplankton communities are vital to oceanic ecosystems. While most are harmless or beneficial, a select group possesses the capability to produce toxins and cause mass die-offs of marine organisms. Florida red tide, caused by blooms of the dinoflagellate Karenia brevis, is common in the Gulf of Mexico, although blooms have been transported to the Atlantic coast and impacted estuaries where K. brevis is not normally found. An in-depth overview of compiled estuary research evaluated the possibility of the continued spread of Florida red tide blooms to Southeastern Atlantic estuaries and the likelihood of establishment in non-native regions. A …

Prioritizing The Largest, Oldest Corals For Disease Intervention In A Coral Disease-Ravaged Area: Southeast Florida Coral Reef Ecosystem Conservation Area, Alysha Brunelle

All HCAS Student Capstones, Theses, and Dissertations

Coral diseases appear to be more devastating than ever before. When a virulent disease ravages a coral ecosystem, it can significantly change the population’s demographics and cause local extinctions. Disease intervention response during such an event is impossible at a landscape scale, therefore priorities must be considered. Saving the largest, oldest colonies of reef-building species is a good choice due to their high fecundity and ecological function. Their size, as a proxy for age, is an indicator of their resistance to previous perturbations which may indicate higher fitness. Their size also provides habitat to many organisms and wave resistance in …

A Shark Conservationists Toolbox: Current Dna Methods And Techniques Aiding In The Conservation Of Sharks, Arianna N. Nixon

All HCAS Student Capstones, Theses, and Dissertations

Elasmobranchs are important members of their community. Many sharks are important apex predators that help maintain the health of their ecosystem. However, shark populations are globally declining. This is partially due to the fact that sharks are highly targeted for their fins, meat, liver oil, teeth, and skin. However, they are also killed from anthropogenic effects such as habitat destruction and pollution. Most shark species have life history characteristics that also make them more vulnerable to overfishing. Sharks are also difficult to study due to their elusive nature and identification issues. That is why molecular tools are increasingly becoming important …

Linking Crude Oil And Dispersant Effects To Gene Expression Of Marine Sponge Cinachyrella, Yvain Desplat

All HCAS Student Capstones, Theses, and Dissertations

Because of their filter-feeding lifestyle, sponges (Phylum Porifera) have shown to be bio-accumulators of heavy metals, and bio-monitors for polychlorobiphenyl (PCB) contaminants. Furthermore, marine sponges have been shown to be regulators of reef ecosystems by fulfilling many ecological functions. However, very little is known about their behavior in the face of environmental changes. Consequently, our lab has developed the reef sponge Cinachyrella spp. as novel experimental model. We have designed an experiment to study the effects of WAF (Water Accommodated Fraction), Corexit 9500 dispersant, and CE-WAF (Chemically Enhanced Water Accommodated Fraction)mixtures, in an effort to mimic the conditions of the …

To Feed Or Not To Feed: Examining The Effects Of Provisioning Tourism On Nurse Sharks In Caye Caulker, Belize, Carlee Jackson

All HCAS Student Capstones, Theses, and Dissertations

Wildlife tourism is increasing in popularity around the world, creating the need to understand alterations in animal behavior and spatial distributions that may occur due to associated anthropogenic disturbances. Nurse sharks (Ginglymostoma cirratum, Bonnaterre 1788) are commonly used for wildlife tourism within the Caye Caulker Marine Reserve in Belize. Shark and Ray Village (SRV) is a site within the reserve where nurse sharks are consistently fed by tour/snorkel boats to create an interactive experience with tourists, termed provisioning tourism. Prior to this experiment, no studies had been conducted in SRV to evaluate the impact of provisioning tourism (tourism …

Connection Between Contaminants And Marine Mammals In The Southern Ocean, Sean W. Tupper

All HCAS Student Capstones, Theses, and Dissertations

The Southern Ocean encircles the continent of Antarctica and was once thought to be unaffected by human activities. However, evidence is increasing that this region has many different contaminants that threaten the region’s marine biodiversity, including marine mammals. Many of these contaminants are heavy metals or persistent organic pollutants and enter the Southern Ocean via both natural and anthropogenic processes. The impacts posed by these contaminants vary according to their type and the organism being exposed. All species of cetaceans and pinnipeds in this study were confirmed to have been exposed to one or more the contaminants reviewed. Although research …

Comparative Study Of Spectral Sensitivity, Irradiance Sensitivity, Spatial Resolution And Temporal Resolution In The Visual Systems Of Aratus Pisonii And Ocypode Quadrata, Ruchao Qian

All HCAS Student Capstones, Theses, and Dissertations

Autrum’s studies (1950, 1958) on terrestrial arthropods first revealed that the visual systems of arthropods reflected their lifestyles and habitats, demonstrating that rapidly moving predatory diurnal species tend to have better temporal resolution than slower moving nocturnal species. In order to test Autrum’s hypothesis that visual adaptions are driven by predator/prey interactions, the visual physiology of a nocturnal fast-moving predatory crab, the Atlantic ghost crab (Ocypode quadrata), and a diurnal herbivorous crab, the mangrove tree crab (Aratus pisonii), was examined and compared. Spectral sensitivity, irradiance sensitivity, and temporal resolution of the crabs were quantified using the …