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2025

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Dynamics Of Prey-Prey Mutualism With Varying Carrying Capacity And Herd Behavior In The Presence Of Predator, Felix Dela Djokoto Jan 2025

Dynamics Of Prey-Prey Mutualism With Varying Carrying Capacity And Herd Behavior In The Presence Of Predator, Felix Dela Djokoto

UNF Graduate Theses and Dissertations

This study investigates the dynamics of mutualistic relationships between two prey species in the presence of a predator, by taking into account herding in one species along with the influence of carrying capacities between two prey species. These mutualistic dynamics are presented by constructing two mathematical models, namely an indirect and direct mutualism model. As the strength of the symbiotic relationship increases the indirect model goes through transcritical bifurcation to Hopf bifurcation whereas in the direct mutualism model goes through saddle-node bifurcation to Hopf bifurcation.

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Severe Aggression Among Zoo-Housed Coconut (Trichoglossus Haematodus) And Rainbow (Trichoglossus Moluccanus) Lorikeets: Wellbeing Considerations For Free-Flight Aviaries, Emily Simkins Jan 2025

Severe Aggression Among Zoo-Housed Coconut (Trichoglossus Haematodus) And Rainbow (Trichoglossus Moluccanus) Lorikeets: Wellbeing Considerations For Free-Flight Aviaries, Emily Simkins

UNF Graduate Theses and Dissertations

As conservation and education institutions, modern zoos balance the needs of animals with the interests of visitors through several strategies which can increase animal wellbeing and improve visitor experience. Environmental enrichment is frequently employed to increase the suitability of anthropogenic environments for zoo-housed animals, such as through walkthrough habitats and free-flight aviaries. While habitats such as these are important for visitor experience and can be enriching to animals, there are also wellbeing considerations for these spaces. Walkthrough habitats can be a potential source of fear and stress for animals, as shown by increased frequencies of vigilance, undesirable behavior, and aggression. …

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What’S For Dinner? A Multi-Pronged Approach Investigating The Foraging Habits And Diet Of St. Johns River Bottlenose Dolphins (Tursiops Erebennus), Andrea Leigh Swinehart Jan 2025

What’S For Dinner? A Multi-Pronged Approach Investigating The Foraging Habits And Diet Of St. Johns River Bottlenose Dolphins (Tursiops Erebennus), Andrea Leigh Swinehart

UNF Graduate Theses and Dissertations

Wildlife population management depends on knowledge of the population’s foraging ecology. A community of resident Tamanend’s bottlenose dolphins (Tursiops erebennus) utilizes the St. Johns River (SJR) in Jacksonville, Florida, and members of the community are regularly sighted emaciated or with skin lesions. Anthropogenic disturbances may contribute to further health decline, therefore Chapter One analyzed SJR foraging dolphin group habitat use before, during, and after a large-scale dredging event known as the Jacksonville Harbor Deepening Project (JHDP). Kernel density estimates (KDEs) of foraging dolphin group sightings were generated to estimate 95% utilization distributions (i.e., foraging home ranges) for three …

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Long-Term Abundance Estimates Of A Northeast Florida Estuarine Dolphin Community: Evaluating The Impacts Of The 2013–2015 Cetacean Morbillivirus Unusual Mortality Event, Allison L. Wilkins Jan 2025

Long-Term Abundance Estimates Of A Northeast Florida Estuarine Dolphin Community: Evaluating The Impacts Of The 2013–2015 Cetacean Morbillivirus Unusual Mortality Event, Allison L. Wilkins

UNF Graduate Theses and Dissertations

Tamanend's bottlenose dolphins (Tursiops erebennus) in the St. Johns River (SJR), Jacksonville, FL, are subjected to substantial anthropogenic stressors (e.g., vessel traffic, dredging, fisheries interactions) and were heavily impacted by the 2013-2015 Mid-Atlantic cetacean morbillivirus unusual mortality event (UME). High prevalence of skin lesions and frequent sightings of emaciated dolphins suggest declining health and viability of the SJR dolphin community. Sighting data from Jul. 2011 to Oct. 2019 provided the rare opportunity to investigate long-term changes in dolphin abundance surrounding the UME. This study produced the first dolphin abundance estimate within the Jacksonville Estuarine System stock since 1997, …

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The Presence Of Mercury (Hg) And Perfluoroalkyl Substances (Pfas) In The Guana And Tolomato Rivers, Morgan E. Lattomus Jan 2025

The Presence Of Mercury (Hg) And Perfluoroalkyl Substances (Pfas) In The Guana And Tolomato Rivers, Morgan E. Lattomus

UNF Graduate Theses and Dissertations

The Guana and Tolomato Rivers provide essential habitat for several ecologically and economically important species and is a well-loved and recreated area. Spanning the northeastern Florida coast, the rivers are home to over 50 endangered or threatened species and host several habitat restoration projects due to their ecological significance and proximity to development along the coast. The effects of human influence and pollution, and specifically toxic metal mercury (Hg) and perfluoroalkyl substances (PFAS), are not well known within the system. Hg is known to biomagnify within food webs, and there is a considerable lack of literature concerning PFAS behavior within …

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