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Full-Text Articles in Life Sciences
A Conservation Model: Costa Rican Conservation Strategies Effectively Preserve Their Threatened Primates, Ryan Belmont
A Conservation Model: Costa Rican Conservation Strategies Effectively Preserve Their Threatened Primates, Ryan Belmont
Regis University Student Publications (comprehensive collection)
The wildlife of Costa Rica has experienced various anthropogenic threats over the last century including climate change and agricultural expansion. The mantled howler monkey (Alloutta palliata), Central American spider monkey (Ateles geoffroyi), white-faced capuchin (Cebus imitator), and the Central American squirrel monkey (Saimiri oerstedii) are Costa Rica’s native primates that face several anthropogenic threats such as deforestation for agriculture and climate change. In response to increased threats to its four native species of non-human primates, Costa Rica has implemented effective governmental conservation tactics such as the Payments for Environmental Services program, ecotourism …
Individual And Population Responses To Hydrologic Variability In A Headwater Stream Salamander, Madaline Cochrane
Individual And Population Responses To Hydrologic Variability In A Headwater Stream Salamander, Madaline Cochrane
Graduate Student Theses, Dissertations, & Professional Papers
Understanding how organisms respond to environmental variability is a central goal in ecology – a goal made even more pressing by the herculean challenge global climate change presents to all organisms. Climate change is increasing the frequency and intensity of floods and droughts, which will likely have disproportionate effects on freshwater organisms. Many stream-associated species have multi-stage life histories. However, we lack an empirical understanding of life history and movement responses of these organisms to hydrologic disturbances, and how these responses may influence demographic rates. In my dissertation, I used a combination of growth, developmental, movement, and demographic data to …
Chromosome Number Evolution, Phylogeography, And The Effects Of Climate Change On Species Distributions In Polyploid Plant Systems, Courtney H. Babin
Chromosome Number Evolution, Phylogeography, And The Effects Of Climate Change On Species Distributions In Polyploid Plant Systems, Courtney H. Babin
University of New Orleans Theses and Dissertations
Polyploidy, a term used to describe organisms with cells having more than two paired sets of chromosomes, is a significant driver of diversification among land plants. Over a century of research has advanced our understanding of polyploidization in some taxa, but polyploid organisms remain understudied. In this dissertation, I investigate chromosome number evolution, phylogeographic structure, genetic differentiation, and the effects of climate change on ploidy level distribution using polyploid plant systems. In the first chapter, I inferred a molecular phylogeny of Allium, an economically important genus that includes cultivated crops and ornamentals, to investigate evolutionary transitions in chromosome number …
The Influence Of Climate Change On The Ecology Of The Arctic Ground Squirrel In Denali National Park, Ak., Nigel A. Golden
The Influence Of Climate Change On The Ecology Of The Arctic Ground Squirrel In Denali National Park, Ak., Nigel A. Golden
Doctoral Dissertations
This dissertation research focuses on the ecology of the Arctic ground squirrel (Urocitellus parryii) in Denali National Park and Preserve, AK. The Arctic ground squirrels is a species of interest for monitoring efforts under the National Park Services’ Vital Signs Monitoring Program under the Vital Signs Monitoring program. The focus of this program is to monitor what is considered to be the most significant indicators of ecological conditions of the specific park resources that are of the greatest concern. The CAKN designated the Arctic ground squirrel (Urocitellus parryii) as one indicator species of park ecosystems. Despite being easy to observe …
The Impacts Of Climate Change On The Gulf Of Maine Northern Shrimp (Pandalus Borealis) Distribution, Reproduction, And Life, Hsiao-Yun Chang
The Impacts Of Climate Change On The Gulf Of Maine Northern Shrimp (Pandalus Borealis) Distribution, Reproduction, And Life, Hsiao-Yun Chang
Electronic Theses and Dissertations
The Gulf of Maine northern shrimp (Pandalus borealis) once supported a significant winter fishery for the Gulf of Maine (GOM). Although the shrimp fishery is not comparable to the lobster business, it provided fishermen and many coastal communities jobs and incomes in winters after lobster seasons. However, a moratorium has been put on the shrimp fishery since 2014 due to record low population abundance and perceived recruitment failures. The recruitment failures have been correlated with warming water temperatures over the past decade. The GOM has been recognized as experiencing rapid warming as a result of global climate change. …
Testing The Climatic Variability Hypothesis With Coastal And Inland Populations Of Mimulus Guttatus And Implications For These Populations Under Climate Change, Alec Chiono
Master's Theses
How climate shapes the niche of a species is a core interest in evolution and ecology. Research on the evolution of climatic niches can inform us on the historical relationship between organisms and their climate, and, in an era of great environmental change, what that relationship may look like in the future. In this study, I tested an essential idea in the history of climate niche research, the Climatic Variability Hypothesis, by comparing the thermal niche breadth of coastal and inland populations of Mimulus guttatus. Using thermal performance results from this experiment, I also forecasted how the suitability of …
The Potential Influence Of Abiotic Conditions On Mussel Species Abundance In San Francisco Bay, Alexandra G. Farrell, M. Christina Vasquez Dr.
The Potential Influence Of Abiotic Conditions On Mussel Species Abundance In San Francisco Bay, Alexandra G. Farrell, M. Christina Vasquez Dr.
Honors Thesis
Climate change has negatively altered seawater conditions, which may have severe implications for marine ecosystems. Mussels are susceptible to environmental changes since they are primary consumers and filter-feeding bivalves. Two species of particular interest to the West Coast of the U.S. are Mytilus galloprovincialis and M. trossulus. M. trossulus is native to the California Coast and was historically prevalent from Southern California to Washington. However, with increased shipping and rising seawater temperature, M. galloprovincialis, an invasive species from the Mediterranean, pushed the species range of M. trossulus poleward. M. trossulus is more tolerant of cold seawater with variable salinity while …
Interacting Effects Of Climate And Biotic Factors On Mesocarnivore Distribution And Snowshoe Hare Demography Along The Boreal-Temperate Ecotone, Alexej P. Siren
Interacting Effects Of Climate And Biotic Factors On Mesocarnivore Distribution And Snowshoe Hare Demography Along The Boreal-Temperate Ecotone, Alexej P. Siren
Doctoral Dissertations
The motivation of my dissertation research was to understand the influence of climate and biotic factors on range limits with a focus on winter-adapted species, including the Canada lynx (Lynx canadensis), American marten (Martes americana), and snowshoe hare (Lepus americanus). I investigated range dynamics along the boreal-temperate ecotone of the northeastern US. Through an integrative literature review, I developed a theoretical framework building from existing thinking on range limits and ecological theory. I used this theory for my second chapter to evaluate direct and indirect causes of carnivore range limits in the northeastern US, …
Sea Level Rise Vulnerability Analysis Of Mangrove Ecosystems Using Gis, Kayla Caldwell
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 …
Biogeography Of Endemic Dragonflies Of The Ozark-Ouachita Interior Highlands, Wade Alexander Boys
Biogeography Of Endemic Dragonflies Of The Ozark-Ouachita Interior Highlands, Wade Alexander Boys
Graduate Theses and Dissertations
A common pattern across many taxonomic groups is that relatively few species are widespread while the majority are restricted in their geographic ranges. Such species distributions are used to inform conservation status, which poses unique challenges for rare or cryptic species. Further, priority status is often designated within geopolitical boundaries, which may include only a portion of a species range. This, coupled with lack of distributional data, has resulted in species being designated as apparently rare throughout some portions of their range, which may not accurately reflect their overall conservation need. The Interior Highlands region of the central United States …
Influence Of Climate Change And Prescribed Fire On Habitat Suitability And Abundance Of The High-Elevation Endemic Cow Knob Salamander (Plethodon Punctatus), Carl David Jacobsen
Influence Of Climate Change And Prescribed Fire On Habitat Suitability And Abundance Of The High-Elevation Endemic Cow Knob Salamander (Plethodon Punctatus), Carl David Jacobsen
Graduate Theses, Dissertations, and Problem Reports
Amphibians are facing global declines due to climate change, loss and degradation of habitat, invasive species, and disease. The Appalachian region of the eastern USA is a global biodiversity hotspot for salamanders, which are considered keystone species that influence nutrient dynamics in terrestrial and aquatic food webs. There are high rates of salamander endemism in the Appalachian region, with many species restricted to isolated, high elevation areas. The Cow Knob Salamander (Plethodon punctatus) is one such species. It is only found at elevations >675 m (most populations are above 900 m) on Shenandoah Mountain, North Mountain, and Nathaniel …
Understanding The Impacts Of Current And Future Environmental Variation On Central African Amphibian Biodiversity, Courtney A. Miller
Understanding The Impacts Of Current And Future Environmental Variation On Central African Amphibian Biodiversity, Courtney A. Miller
University of New Orleans Theses and Dissertations
Global climate change is projected to impact multiple levels of biodiversity by imposing strong selection pressures on existing populations, triggering shifts in species distributions, and reorganizing entire communities. The Lower Guineo-Congolian region in central Africa, a reservoir for amphibian diversity, is predicted to be severely affected by future climate change through rising temperatures and greater variability in rainfall. Geospatial modelling can be used to assess how environmental variation shapes patterns of biological variation – from the genomic to the community level – and use these associations to predict patterns of biological change across space and time. The overall goal of …
Gyrfalcon Diet During The Brood Rearing Period On The Seward Peninsula, Alaska, In The Context Of A Changing World, Bryce W. Robinson
Gyrfalcon Diet During The Brood Rearing Period On The Seward Peninsula, Alaska, In The Context Of A Changing World, Bryce W. Robinson
Boise State University Theses and Dissertations
As climate change impacts increase so does our need to understand their effects on ecosystem dynamics. I studied Gyrfalcon (Falco rusticolus) diet during the brood rearing period to improve our knowledge on dietary habits during nesting, and provide necessary information for understanding climate change impacts to Arctic ecosystems. I studied diet over two breeding seasons on the Seward Peninsula, Alaska, using two methods: motion-activated cameras and the collection of prey remains. I observed three important dietary shifts: the proportion of ptarmigan in the diet declined significantly throughout the season, the proportion of large prey items declined significantly throughout …
Integrated Modeling Of Land Use And Climate Change Impacts On Multiscale Ecosystems Of Central African Watersheds, Simon Nampindo
Integrated Modeling Of Land Use And Climate Change Impacts On Multiscale Ecosystems Of Central African Watersheds, Simon Nampindo
Doctoral Dissertations
Assessment and management of ecosystem services demands diverse knowledge of the system components. Land use change occurring mainly through deforestation, expansion of agriculture and unregulated extraction of natural resources are the greatest challenges of the Congo basin and yet is central to supporting over 100 million people. This study undertook to implement an integrated modeling of multiscale ecosystems of central African watersheds and model the impact of anthropogenic factors on elephant population in Greater Virunga landscape. The study was conducted at varied scales, regional, landscape, and community. Regional study included watershed analysis and hydrological assessment using remotely sensed data implemented …
Population Response To Climate Change: Wintering Strategy Has Carryover Effects On The Timing Of Nest Initiation And Mate Choice In A Partial Migrant, The American Kestrel (Falco Sparverius), Alexandra Marie Anderson
Population Response To Climate Change: Wintering Strategy Has Carryover Effects On The Timing Of Nest Initiation And Mate Choice In A Partial Migrant, The American Kestrel (Falco Sparverius), Alexandra Marie Anderson
Boise State University Theses and Dissertations
The ability of a population to respond to climate change will depend on phenotypic plasticity, adaptation, or both. Bird populations have already responded to warming temperatures by shifting their distributions, adjusting migration distance and timing, and breeding earlier. A population of American kestrels (Falco sparverius) in southwestern Idaho has advanced its nesting by approximately 30 days, on average, in the last 30 years and this has been correlated with changes in winter climate. The mechanisms allowing for this shift, however, are not clearly understood. I investigated if assortative mating of wintering kestrels and non-wintering kestrels is accompanying to …