Open Access. Powered by Scholars. Published by Universities.®

Life Sciences Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 12 of 12

Full-Text Articles in Life Sciences

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 …


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 …


Psammocora Stellata Distribution At Devil's Crown, Floreana Island, Galápagos Islands, Ecuador, María José Guarderas Sevilla Dec 2023

Psammocora Stellata Distribution At Devil's Crown, Floreana Island, Galápagos Islands, Ecuador, María José Guarderas Sevilla

All HCAS Student Capstones, Theses, and Dissertations

In the Galápagos Archipelago, the free-living nodular coral Psammocora stellata is a common species that does not form reef structures. However, it is a key component of the ecosystem by increasing habitat complexity and, consequently, species diversity. This species experienced a drastic decline in Devil’s Crown channel, Floreana Island, where it disappeared after the 1982-83 El Niño-Southern Oscillation, presumably by displacement of unattached colonies by strong surface waves and currents. This assemblage has now recovered to pre-impact levels. A combination of underwater photoquadrats from 2007 and 2009 and recent (2023) orthomosaics were used to determine changes in coral densities 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 …


Taxonomic Resolution Assessment And Biodiversity Evaluations For Deep-Sea Fish Assemblages In A Pelagic Ecosystem Of The Northern Gulf Of Mexico, Krista N. Scheuerman Aug 2022

Taxonomic Resolution Assessment And Biodiversity Evaluations For Deep-Sea Fish Assemblages In A Pelagic Ecosystem Of The Northern Gulf Of Mexico, Krista N. Scheuerman

All HCAS Student Capstones, Theses, and Dissertations

Knowledge of community assemblages and biodiversity is important for monitoring health and resilience in an ecosystem. Taxonomic and functional biodiversity of mesopelagic (200- 1000 m) fishes is extremely rich in the Gulf of Mexico. The aim of this study was to compare calculations of biodiversity and community structures at varying taxonomic resolutions for deep pelagic fishes to inform future decisions about deep-sea ecosystem monitoring. This study analyzed biodiversity and assemblage structure patterns from a biological inventory of deep-sea fishes collected with a large mesh, commercial-sized, high-speed rope trawl in the Gulf of Mexico between June 21st and July 14 …


Benthic Community Dynamics And Stony Coral Demographics In Florida In Relation To Acute Disturbances And Chronic Pressures, Nicholas P. Jones Aug 2022

Benthic Community Dynamics And Stony Coral Demographics In Florida In Relation To Acute Disturbances And Chronic Pressures, Nicholas P. Jones

All HCAS Student Capstones, Theses, and Dissertations

The persistence of coral reef communities is threatened by a suite of pressures operating at varying spatial and temporal scales. In general, acute disturbances (short term stochastic events such as marine heatwaves or hurricanes) and chronic pressures, such as ocean warming, have caused the most significant changes to stony coral assemblages (order Scleractinia) and continue to impair recovery potential. Additionally, many coral reefs are subject to local chronic anthropogenic pressures resulting in poor water quality or sedimentation, which further impact stony corals and shape benthic community structure, particularly near urbanized coastlines. For the viability of communities on coral reefs, a …


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 …


Prioritizing The Largest, Oldest Corals For Disease Intervention In A Coral Disease-Ravaged Area: Southeast Florida Coral Reef Ecosystem Conservation Area, Alysha Brunelle Aug 2020

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 …


Sea Level Rise Vulnerability Analysis Of Mangrove Ecosystems Using Gis, Kayla Caldwell Apr 2020

Sea Level Rise Vulnerability Analysis Of Mangrove Ecosystems Using Gis, Kayla Caldwell

HCNSO Student Theses and Dissertations

Climate change is accelerating beyond what is natural due to excessive emissions from human activities. The sea level has been rising for many years and is currently at a rate of 3.6 mm/yr. Mangroves are known to only keep pace with a sea level rate of less than 1.2 mm/yr. Mangroves are particularly vulnerable to rising sea levels if they are not able to keep pace through vertical sediment accretion or inland migration. To test the vulnerability of the south Florida mangrove ecosystems to sea level rise, this study analyzed changes in the mangrove forest coverage of the Oleta River …


Evaluating The Ecological Status Of The Introduced Nile Monitor (Varanus Niloticus) In Florida: Forecasting Presence And Population Expansion Using Computational Geographic Information Systems, Noah G. Cohen Nov 2017

Evaluating The Ecological Status Of The Introduced Nile Monitor (Varanus Niloticus) In Florida: Forecasting Presence And Population Expansion Using Computational Geographic Information Systems, Noah G. Cohen

HCNSO Student Theses and Dissertations

The Nile monitor (Varanus niloticus) is a large, carnivorous lizard that has become a notorious invasive species in Florida, USA. Initially released in the 1980s from the pet trade, the species has since established at least three breeding populations and spread throughout much of southern Florida. While current control efforts have failed to eradicate V. niloticus, it is important to attain a better understanding of its invasive dynamics to guide and inform better control strategies. In this study, available georeferenced records of V. niloticus in Florida were compiled and linked to a habitat classification map to evaluate ecotype preferences. Factored …


Sea Turtle Conservation: Reviewing The Efficacy Of Land- And Sea-Based Management Strategies For Loggerhead (Caretta Caretta) And Leatherback (Dermochelys Coriacea) Sea Turtles, Glenn D. Goodwin Apr 2016

Sea Turtle Conservation: Reviewing The Efficacy Of Land- And Sea-Based Management Strategies For Loggerhead (Caretta Caretta) And Leatherback (Dermochelys Coriacea) Sea Turtles, Glenn D. Goodwin

HCNSO Student Capstones

As cosmopolitan species, loggerhead and leatherback turtles are confronted with a multitude of threats as they progress through their respective life stages. These range from depredation and poaching of eggs, hatchlings, and females on nesting beaches, to incidental hooking in pelagic longline fisheries and capture in trawl fisheries. Some threats are species specific on regional scales, though most impact both species. To confront these threats, various conservation strategies have been developed and implemented, including monitoring and caging of nests and changes to hook shape and trawl design. Here, current conservation methods are presented and discussed on a global scale for …


Reef Fish Spatial Distribution And Benthic Habitat Associations On The Southeast Florida Reef Tract, Dana Fisco Apr 2016

Reef Fish Spatial Distribution And Benthic Habitat Associations On The Southeast Florida Reef Tract, Dana Fisco

HCNSO Student Theses and Dissertations

The Florida Reef Tract (FRT) extends from the tropical Caribbean up the southeast coast of Florida into a temperate environment where tropical reef assemblages diminish with increasing latitude. This study used data from a three-year comprehensive fishery-independent survey to quantify reef fish spatial distribution along the Southeast FRT and define where the assemblage shifts from tropical to temperate. A total of 1,676 reef fish visual census samples were conducted to assess the populations on a stratified-random selection of sites of marine hardbottom habitats between the Miami River and St. Lucie inlet. Multivariate analyses were used to investigate differences in assemblages …