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Trophic Ecology Of Black Swallowers (Scombriformes: Chiasmodontidae: Chiasmodon) In The Deep-Pelagic Gulf Of Mexico, Travis J. Kirk Apr 2024

Trophic Ecology Of Black Swallowers (Scombriformes: Chiasmodontidae: Chiasmodon) In The Deep-Pelagic Gulf Of Mexico, Travis J. Kirk

All HCAS Student Capstones, Theses, and Dissertations

The ecology of deep-pelagic predatory fishes remains poorly understood despite their importance as ecosystem regulators and energy transfer vectors. This study investigated the trophic ecology of three species of the predatory fish genus Chiasmodon (“black swallowers”) in the Gulf of Mexico, a region that serves as an analog for the global low-latitude deep pelagial, the world’s largest cumulative ecosystem. Foraging habits (e.g., selectivity, chronology, daily ration) of an “advanced” evolutionary fish in a system that is otherwise dominated by basal fish taxa, were quantitatively estimated via high-resolution stomach content analysis. A quantitative dataset of both predator and prey abundance, the …


Microplastic Quantification On The Effect Of Endoparasite Communities In Florida Seabirds, Sarah N. Prieto Apr 2024

Microplastic Quantification On The Effect Of Endoparasite Communities In Florida Seabirds, Sarah N. Prieto

All HCAS Student Capstones, Theses, and Dissertations

Microplastics are being studied in a variety of different projects to better understand their impact and threat to wildlife species. Although there is an understanding that microplastics are affecting our wildlife, there are still questions about how coastal seabirds come to ingest them and how the ingestion is altering critical biological processes, such as that for endoparasite communities. This project aims to determine a better understanding of two main objectives: assessment of the presence of secondary ingestion of microplastics in coastal seabirds due to the fish species they prey on and relationship between microplastics and endoparasite communities' structure and state …


Addressing Water Hyacinth (Pontederia Crassipes) Impacts On Aquatic Biota In Lake Okeechobee, Joseph Salerno Dec 2023

Addressing Water Hyacinth (Pontederia Crassipes) Impacts On Aquatic Biota In Lake Okeechobee, Joseph Salerno

All HCAS Student Capstones, Theses, and Dissertations

The incursion of water hyacinth, Pontederia crassipes in Lake Okeechobee has resulted in management systems to be implemented to reduce the coverage of the invasive macrophyte. Its residence in the Lake Okeechobee ecosystem and the effects it has on organisms in the lake, whether it be positive or harmful is unknown. This study attempted to assess the potential effects that water hyacinth has on aquatic biota in Lake Okeechobee. Biotic data were collected on open water, water hyacinth covered, and native vegetation covered habitats via hook-and-line fishing, electrofishing, baited minnow traps, and the sampling of plant roots over a thirteen-month …


Desperate Larva Or Death Before Dishonor: Can Old Coral Larvae Replenish Degraded Reefs?, Nepsis García Lara Aug 2023

Desperate Larva Or Death Before Dishonor: Can Old Coral Larvae Replenish Degraded Reefs?, Nepsis García Lara

All HCAS Student Capstones, Theses, and Dissertations

The recovery of coral populations depends largely on larval recruitment. Coral larvae settle in response to environmental cues that indicate habitat quality. Newly competent larvae typically avoid settling on substrates with high macroalgal cover and sedimentation, and thus might never recruit to degraded reefs, hindering their recovery. What is unknown is if settlement preferences change as larvae age. In the absence of suitable settlement cues, lecithotrophic larvae delay settlement and might do this until either dying (Death Before Dishonor Hypothesis) or becoming less discriminatory and settling regardless of their specific habitat requirements (Desperate Larva Hypothesis). To test these hypotheses in …


The Effect Of Water Flow Rates On The Survival And Growth Rates Of Three Caribbean Bouldering Coral Species Juveniles In An Indoor Versus Outdoor Environment, Ian Michael Johnson Aug 2023

The Effect Of Water Flow Rates On The Survival And Growth Rates Of Three Caribbean Bouldering Coral Species Juveniles In An Indoor Versus Outdoor Environment, Ian Michael Johnson

All HCAS Student Capstones, Theses, and Dissertations

Coral reefs are vital ecosystems for the world’s oceans and humanity; however, they are threatened by climate change, disease, and local anthropogenic stressors, and need assistance to recover. Traditional reef restoration efforts (fragmentation and outplanting are helping but are limited in effectiveness by not increasing genetic diversity. Ex situ sexual propagation for corals provides new, genetically different coral recruits. However, this process is laborious, expensive and time consuming, especially at the scale required to effectively contribute to the widespread recovery. To lower costs, two key parameters that require optimization to hasten the growth of coral recruits are water flow and …


Assessing The Dynamics Of The Southeast Florida Shark Community From 2013-2019 Via Catch Per Unit Effort And Stable Isotope Analysis, Alexandra Barth Apr 2023

Assessing The Dynamics Of The Southeast Florida Shark Community From 2013-2019 Via Catch Per Unit Effort And Stable Isotope Analysis, Alexandra Barth

All HCAS Student Capstones, Theses, and Dissertations

Sharks, as well as other top predators, are in drastic decline worldwide. As apex and near-apex predators, species such as nurse, lemon, and tiger sharks maintain balanced marine ecosystems by enacting top-down trophic control. However, this cascading effect is diminished with exploitation via commercial and recreational fishing. Sharks are generally long-lived, mature late, have long reproductive cycles, and produce few offspring. Much remains to be learned about the community structure, population trends and conservation statuses of shark populations worldwide. Comprehensive studies on the composition of the shark community in Southeast Florida north of Miami have been limited. This study assessed …


Age And Growth For Three Members Of The Family Gempylidae: Escolar (Lepidocybium Flavobrunnuem), Oilfish (Ruvettus Pretiosus), And Snake Mackerel (Gempylus Serpens), Sydney N. Daniels Apr 2023

Age And Growth For Three Members Of The Family Gempylidae: Escolar (Lepidocybium Flavobrunnuem), Oilfish (Ruvettus Pretiosus), And Snake Mackerel (Gempylus Serpens), Sydney N. Daniels

All HCAS Student Capstones, Theses, and Dissertations

Escolar, Lepidocybium flavobrunnuem (Smith, 1849), Oilfish, Ruvettus pretiosus (Cocco, 1829), and Snake Mackerel, Gempylus serpens (Cuvier, 1829) belong to the family Gempylidae and are bycatch of the tuna-targeting pelagic longline fishery. There is limited know life-history information on these mesopelagic fishes, especially regarding growth rates. Age estimates were assigned by counting pairs of increment bands formed on the sagittal otoliths of Escolar (n = 133), Oilfish (n = 49), and Snake Mackerel (n = 46) collected between 2007 and 2022. Marginal increment analyses were used to validate age estimates and periodicity of increment formation, but no significant trends were observed …


Crustacean Assemblage Structure Over The Charlie-Gibbs Fracture Zone Of The Mid-Atlantic Ridge Collected During The 2009 Henry B. Bigelow Expedition, Kathryn Medina Dec 2022

Crustacean Assemblage Structure Over The Charlie-Gibbs Fracture Zone Of The Mid-Atlantic Ridge Collected During The 2009 Henry B. Bigelow Expedition, Kathryn Medina

All HCAS Student Capstones, Theses, and Dissertations

The Charlie Gibbs Fracture Zone (CGFZ) consists of two nearly parallel fracture transform faults that intersect the Mid-Atlantic Ridge (MAR) axis. This area has high primary productivity and biomass levels due to the topography and water. A predominant hydrographic feature of the MAR is the Sub-Polar Front (SPF) which runs along the southern edge of the CGFZ and is known as a biogeographical boundary for multiple species. As part of The Census of Marine Life project Patterns and Processes of the Ecosystem of the northern Mid-Atlantic (MAR-ECO), this study analyzed the abundance and distribution patterns of the CGFZ crustacean community …


Impacts On Fast-Start Performance: How Do Group Size And Habitat Degradation Alter The Escape Behavior Of A Schooling Coral Reef Fish?, Monica D. Bacchus Aug 2022

Impacts On Fast-Start Performance: How Do Group Size And Habitat Degradation Alter The Escape Behavior Of A Schooling Coral Reef Fish?, Monica D. Bacchus

All HCAS Student Capstones, Theses, and Dissertations

Escaping predation is essential for species survival, but prey must effectively match their response to the perceived threat imposed by a predator. Fish evaluate their surroundings using several sensory stimuli, including olfactory, visual, auditory, and mechanical cues. A range of taxa use the fast-start response to evade predators, including fishes, sharks, and larval amphibians. While the fast-start response (rapid bursts of swimming) is extensively studied in solitary fishes, the factors that mediate the collective escape response in schools of fish have historically been investigated far less. To address this knowledge gap, the collective escape behavior and individual escape performance of …


Feeding Ecology Of Highly Migratory Epipelagic Offshore Predators In The Western North Atlantic Ocean, Rachel Lorraine Hildebrand Aug 2022

Feeding Ecology Of Highly Migratory Epipelagic Offshore Predators In The Western North Atlantic Ocean, Rachel Lorraine Hildebrand

All HCAS Student Capstones, Theses, and Dissertations

Describing trophic ecology of top predators in marine ecosystems is key to understanding the dynamics of these environments. Feeding ecologies of large predatory fishes were assessed using a combination of stomach content and stable isotope analysis. The target species for this study inhabit the epipelagic ecosystem of the U.S. South Atlantic Bight in the western North Atlantic Ocean. The studied species included five tuna species, five billfish species, Common Dolphinfish, and Wahoo. The goal of this study was to describe and compare the trophic dynamics of each species. From these data, the trophic complex of the offshore pelagic ecosystem was …


Abundance, Site-Fidelity, And Association Patterns Of Coastal Bottlenose Dolphins (Tursiops Truncatus) Off Southeast Florida, Graysen D. Boehning Jul 2022

Abundance, Site-Fidelity, And Association Patterns Of Coastal Bottlenose Dolphins (Tursiops Truncatus) Off Southeast Florida, Graysen D. Boehning

All HCAS Student Capstones, Theses, and Dissertations

The coastal bottlenose dolphin is well studied throughout its natural range, however, most of the study areas comprised wide, well-protected habitats such as bays and estuaries, and not narrow coastal sandbanks. This study identifies a residential group of coastal bottlenose dolphins utilizing the narrow sandbanks within the Northwestern Atlantic waters off the coast of Palm Beach County, Florida, USA. From 2014-2020, 313 boat surveys were conducted, and 585 individual dolphins were identified using photo-ID. Twenty-four animals were determined to be full-time and 66 animals were determined to be part-time residents. Full-time and part-time residents associated in three social tribes, with …


The Microbiome Characterization And Comparison Of Loggerhead (Caretta Caretta) And Green (Chelonia Mydas) Sea Turtle Eggs In Broward County, Florida, Colleen Mcmaken Apr 2022

The Microbiome Characterization And Comparison Of Loggerhead (Caretta Caretta) And Green (Chelonia Mydas) Sea Turtle Eggs In Broward County, Florida, Colleen Mcmaken

All HCAS Student Capstones, Theses, and Dissertations

All seven extant species of sea turtles are classified as threatened or endangered due to natural and anthropogenic impacts. Sea turtle conservation efforts are largely dedicated to ensuring healthy nesting activity. Hatching success of sea turtle eggs can be affected by several factors including the proliferation of pathogenic microbes. However, it is unclear as to which microbes have the most impact on hatching success and how they are transmitted into the eggs. The primary aims of this study characterized and compared the bacterial communities (microbiomes) from the i) cloaca of nesting sea turtles; ii) sand within and surrounding the nests …


Accumulation Of Persistent Organic Pollutants In Marine Mammals: A Case Study On Cetaceans, Pinnipeds, And Sirenians, Alydia Moorhead Apr 2022

Accumulation Of Persistent Organic Pollutants In Marine Mammals: A Case Study On Cetaceans, Pinnipeds, And Sirenians, Alydia Moorhead

All HCAS Student Capstones, Theses, and Dissertations

Persistent organic pollutants (POPs) are lipophilic semi-volatile organic chemicals that present a range of challenges to marine biota, specifically marine mammals that often occupy a high trophic position in the food web. POPs have become a global problem since they have been shown to cause immunologic, teratogenic, carcinogenic, neurological, and reproductive complications in living organisms due to their resistance to biodegradation and their lipophilic nature. Marine mammals can accumulate these toxic substances through direct ingestion, trophic transfer, adsorption, and maternal offloading. They are susceptible to both bioaccumulation and biomagnification of POPs. Accumulation of POPs is affected by many variables, including …


Spatiotemporal Variation Of An Eastern Tropical Pacific Pelagic Community Assessed With Free-Drifting Bruvs, Tyler Stephen Plum Dec 2021

Spatiotemporal Variation Of An Eastern Tropical Pacific Pelagic Community Assessed With Free-Drifting Bruvs, Tyler Stephen Plum

All HCAS Student Capstones, Theses, and Dissertations

Information about pelagic community diversity and ecology generally lags far behind that of coastal communities, and largely derives from fisheries data that do not reflect small and non-target species. We describe spatiotemporal vertebrate species diversity and variability over a 3,486 km2 area of highly productive pelagic marine ecosystem in Pacific Panama using drifting baited remote underwater video stations (BRUVS), a non-invasive fishery-independent sampling technique. We observed 26 taxa from 17 families, including 1 mammal, 3 reptile, 5 elasmobranch, and 17 teleost species. Community assemblages differed on and off the continental shelf and between wet (April – December) and dry …


The Age And Growth Of The Yellow Stingray (Urobatis Jamaicensis) In Southeast Florida, Jessica Schieber Aug 2021

The Age And Growth Of The Yellow Stingray (Urobatis Jamaicensis) In Southeast Florida, Jessica Schieber

All HCAS Student Capstones, Theses, and Dissertations

The yellow stingray, Urobatis jamaicensis (Cuvier 1816), is a coastal species that has limited known life-history information, especially regarding their age and growth patterns. Age estimates were assigned by counting band-pairs deposited on the vertebral centrum of stingrays caught between 2003 and 2019 (n = 195). Marginal increment analysis of different size classes was used to validate age estimates, with the largest class having verified annual band deposition (ANOVA, F(9,7), P = 0.029). Age estimates ranged between females, and rates, but females attained larger sizes with the largest observed DW being 241-mm and 216-mm for females and males, respectively. …


Assessment Of Monochloramine Toxicity On Three Small Coastal Organisms, Ashley K. Le Jan 2021

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 Jan 2021

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 …


Investigation Of Sulfur Cycling In Marine Sponge Cinachyrella Spp. From A South Florida Reef, Shelby K. Cain Dec 2020

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 …


Functional Review And Macrostructure Of The Caecum In Ardeidae, Lola R. Mildren Nov 2020

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 …


Algal Coverage Detection And Classification Using Envi: Correlation With Dissolved Oxygen Levels In Elkhorn Slough, Ca, Jason Dawson Aug 2020

Algal Coverage Detection And Classification Using Envi: Correlation With Dissolved Oxygen Levels In Elkhorn Slough, Ca, Jason Dawson

All HCAS Student Capstones, Theses, and Dissertations

Estuaries are exposed to varying stressors, whether they be physical, chemical, or environmental. The most notable of stressors is eutrophication of coastal and inland ecosystems. This is a result of increased supply of nutrients fueling production within the system. One outcome of this increased nutrient load to the system is that of algal blooms. These blooms can impact the aesthetic appearance and degrade the quality of health of the system. Many of these coastal zones and waterways are critical habitats for many biological (some endangered) species and serve as recreational areas for human populations. Elkhorn Slough, California is one of …


To Feed Or Not To Feed: Examining The Effects Of Provisioning Tourism On Nurse Sharks In Caye Caulker, Belize, Carlee Jackson Aug 2020

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 Jul 2020

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 …