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An Acoustic Monitoring Method For Assessing River Dolphin Presence And Changes In The Context Of Anthropogenic Development, Charles A. Muirhead Dec 2018

An Acoustic Monitoring Method For Assessing River Dolphin Presence And Changes In The Context Of Anthropogenic Development, Charles A. Muirhead

Graduate Masters Theses

Populations of river dolphins throughout Asia are in decline as a direct result of intensified anthropogenic activity along river systems. Water development projects, land use change, contamination, and intensified fishing practices are known factors contributing to the probable extinction of the Yangtze river dolphin (Lipotes vexillifer) and declining populations of the South Asian river dolphin (Platanista gangetica spp.), Irrawady dolphin (Orcaella brevirostris), and finless porpoise (Neophocaena a. asiaeorientalis). Although not yet as extensive, river system development in South America is following a similar path as that of Asia, with impacts on dolphin species likely to follow. Currently, the Amazon river …


Understanding The Impacts Of Current And Future Environmental Variation On Central African Amphibian Biodiversity, Courtney A. Miller Dec 2018

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 …


Delineating Metrics Of Diversity For A Snake Community In A Rare Ecosystem, Zachary John Marcou Aug 2018

Delineating Metrics Of Diversity For A Snake Community In A Rare Ecosystem, Zachary John Marcou

Electronic Theses and Dissertations

Snakes are among the least understood vertebrate groups despite their considerable diversity. A diverse community of snakes in an ecosystem can indicate a complex habitat structure that is capable of supporting a robust assemblage of other biota. I used remote photography arrays (RPA) to quantify metrics of diversity for the snake community occurring in a ~7,000–ha tract of contiguous Longleaf Pine (Pinus palustris) Savanna within the Angelina National Forest (ANF; Angelina and Jasper Cos., TX), over the course of two consecutive snake activity seasons. I quantified the snake species richness, Shannon diversity, and Shannon equitability for the snake community in …


Using Anthropogenic Risks To Inform Salmonid Conservation At The Landscape Scale, Andrew W. Witt Aug 2018

Using Anthropogenic Risks To Inform Salmonid Conservation At The Landscape Scale, Andrew W. Witt

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The expansion and industrialization of humanity has caused many unforeseen consequences to the natural world. Due to the importance of freshwater for people, rivers have been particularly altered to meet human needs, often at the expense of the natural world. Supplying water for farms, industries, and cities has reshaped the natural state of rivers by altering river paths, chemistry, and species compositions. These changes have harmed many species that prospered before widespread human alterations, including the native trout and salmon of western North America. As human populations continue to grow, new threats will surface for rivers, and the trout and …


Conservation Of Freshwater Live-Bearing Fishes: Development Of Germplasm Repositories For Goodeids, Yue Liu Jul 2018

Conservation Of Freshwater Live-Bearing Fishes: Development Of Germplasm Repositories For Goodeids, Yue Liu

LSU Doctoral Dissertations

Fishes of the family Goodeidae are considered to be among the most imperiled taxa in the world. The goal of this project was to provide a foundation for development of sperm repositories for goodeids and to use them as a model to assist conservation programs for imperiled freshwater live-bearing fishes. Development of such repositories is challenging because of unusual reproductive characteristics of live-bearing fishes, such as sperm bundles, internal fertilization, and the bearing of live young. Standardized methods were established to evaluate quality-related attributes of sperm bundles. The different features between activation of free and bundled sperm were investigated and …


Genetic Population And Evolutionary Dynamics Of The Angel Sharks, Squatina Spp., Cristin Keelin Fitzpatrick May 2018

Genetic Population And Evolutionary Dynamics Of The Angel Sharks, Squatina Spp., Cristin Keelin Fitzpatrick

HCNSO Student Theses and Dissertations

Once so abundant as to be called the ‘common’ angelshark, Squatina squatina has been extirpated from nearly the entirety of its historical range, from the eastern North Atlantic, to the Mediterranean Sea [International Union for the Conservation of Nature (IUCN) Red List: Critically Endangered]. The angelshark now only occurs in any abundance in the waters surrounding the Canary Islands. I present the first genetic assessment of the angelshark’s population dynamics and diversity from three locations within the Canary Islands archipelago: Gran Canaria, Tenerife, and Lanzarote. Using a suite of individual mitochondrial genome regions [Control region (CR), NADH dehydrogenase subunit 2 …


Sibship Reconstruction For Inferring The Number Of Breeders Of Gulf Sturgeon In The Apalachicola River, Robbilyn Verges May 2018

Sibship Reconstruction For Inferring The Number Of Breeders Of Gulf Sturgeon In The Apalachicola River, Robbilyn Verges

Honors Theses

The Gulf sturgeon is an anadromous fish that inhabits the Gulf of Mexico and its neighboring river drainages. The species is currently listed as threatened due to habitat alterations and overfishing. In this study, we focused on the Apalachicola River in Florida, which has had several historic spawning locations of the sturgeon blocked by the Jim Woodruff Lock and Dam. Age-1 juvenile sturgeon from the year 2013 (n=31) and 2014 (n=131) were genotyped using fourteen microsatellite loci. Sibship reconstruction and parentage assignment was performed in order to determine the effective number of breeders (Nb) and the total number of spawning …


Critical Habitat Assessment And Recovery Plan For The Kansas State Threatened Broad-Headed Skink, Allison Hullinger May 2018

Critical Habitat Assessment And Recovery Plan For The Kansas State Threatened Broad-Headed Skink, Allison Hullinger

Master's Theses

No abstract provided.


Genetic Estimates Of The Number Of Breeding Adults In Alligator Gar From The Choke Canyon Reservoir, Texas, E. Blayne Newsome May 2018

Genetic Estimates Of The Number Of Breeding Adults In Alligator Gar From The Choke Canyon Reservoir, Texas, E. Blayne Newsome

Honors Theses

Alligator gar were historically found across the coastal drainages of the Gulf of Mexico and up into the Mississippi River basin. However, their populations are experiencing decline in many portions of their range. Texas seems to have large populations of alligator gar, but state resource officers are seeking to better understand its biology so as to provide appropriate management recommendations to maintain the recreational fishery. In this study, I used genetic techniques to examine a cohort of 144 juvenile alligator gar collected in 2016 in the Choke Canyon Reservoir. By estimating the effective number of breeders and number of spawning …


Militarization Of Conservation, Daniel Ryan Michel Feb 2018

Militarization Of Conservation, Daniel Ryan Michel

Dissertations, Theses, and Capstone Projects

The world is facing biological diversity extinction of its wildlife solely caused by humans. One of the leading causes of the extinction crisis is attributed to poaching and the illegal trade of wildlife products. In search of finding suitable methods to curb the crisis, a dichotomy of overarching solutions has arisen: those who have advocated for community-based natural resource management and those who support militarized conservation. The focus of this paper is to delineate which method is, if any, the most appropriate when combatting poaching and the illegal wildlife trade. Concentrating on elephants (both African and Asian) and the rhinoceros, …


Biodiversity And Evolution In The Guiana Shield, South America, Andrew Michael Snyder Jan 2018

Biodiversity And Evolution In The Guiana Shield, South America, Andrew Michael Snyder

Electronic Theses and Dissertations

The neotropics are characterized as the most species rich region in the world. Unfortunately, the region's unparalleled biodiversity has not protected it from ongoing threats such as agriculture, mining, logging, oil extraction, and climate change. I studied the biodiversity and evolution of the herpetofauna of South America in order to investigate the influence of historical geological and climatological events in shaping extant neotropical diversity, particularly the Guiana shield. For my research, I set out to explore the processes involved in shaping the remarkable extant diversity using anuran amphibians as models. With my dissertation, I provide a comprehensive review of the …


A Case-Study Of The African Leopard (Panthera Pardus Pardus) Population On The Nambiti Private Game Reserve, Erica Castaneda Jan 2018

A Case-Study Of The African Leopard (Panthera Pardus Pardus) Population On The Nambiti Private Game Reserve, Erica Castaneda

Honors Undergraduate Theses

The Nambiti Private Game Reserve in KwaZulu-Natal, South Africa is a nature reserve that aids in the conservation of some of the world’s most renown species. This includes members of the "Big Five," which is comprised of the African lion (Panthera leo), the African elephant (Loxidonta africana), the Cape buffalo (Syncerus caffer), the black & white rhinoceroses (Diceros bicornis and Ceratotherium simum, respectively), and the African leopard (Panthera pardus pardus). These animals represent the top five African animals desired by trophy hunters and by tourists hoping to view wildlife (Caro …


Evaluating Elasmobranch Bycatch And Shark Depredation In The Georgia Shrimp Fishery, Matthew M. Scanlon Jan 2018

Evaluating Elasmobranch Bycatch And Shark Depredation In The Georgia Shrimp Fishery, Matthew M. Scanlon

Electronic Theses and Dissertations

The Georgia shrimp fishery has seen a dramatic decrease in profit and productivity since the 1980’s due to a number of economic factors. Additional, yet undocumented, pressures on this fishery include interactions between foraging sharks with trawl gear. Fishermen report that sharks frequently bite nets in an attempt to prey on netted fish, resulting in large holes in the gear. Further elasmobranch interactions with trawl gear occur as bycatch; shrimp trawls represent nearly 100% of elasmobranch commercial bycatch in Georgia state waters, the species composition of which is largely unstudied. Shark interactions with nets were detailed through fishery-dependent observations on …


Demography And Dendrochronology Of A Disjunct Population Of Eastern Hemlock In Southwestern Ohio, Marie Johnson Jan 2018

Demography And Dendrochronology Of A Disjunct Population Of Eastern Hemlock In Southwestern Ohio, Marie Johnson

Browse all Theses and Dissertations

Edge and isolated plant populations provide information about the resilience and the most basic resource needs of a species. Plant demography examines changes in population size and structure over time. An isolated, disjunct eastern hemlock population in Clifton Gorge State Nature Preserve, Yellow Springs, Ohio consists of two distinct subpopulations each with different environmental characteristics, reproductive capacities, and health ratings. Both subpopulations at Clifton Gorge were found to exhibit significant decreases in average annual ring width through time. Linear regression modeling determined that average annual growing season precipitation and temperature were the strongest predictors of these growth trends. A comparative …


Evidence For The Genetic Basis And Inheritance Of Ocean And River-Maturing Ecotypes Of Pacific Lamprey (Entosphenus Tridentatus) In The Klamath River, California, Keith A. Parker Jan 2018

Evidence For The Genetic Basis And Inheritance Of Ocean And River-Maturing Ecotypes Of Pacific Lamprey (Entosphenus Tridentatus) In The Klamath River, California, Keith A. Parker

Cal Poly Humboldt theses and projects

Surveys of genetic variation have improved our understanding of the relationship between fitness-related phenotypes and their underlying genetic basis. However, how this information can be used to inform conservation has been unclear in many cases. The objective of this study was to combine next-generation genetic sequencing with traditional ecological knowledge to evaluate imperiled anadromous Pacific lamprey (Entosphenus tridentatus) and apply the findings to conservation in the context of resolving Native American traditional food security issues. In the Klamath River of California, a previously identified Pacific lamprey ocean-maturing ecotype was distinguished by a relatively advanced maturity of female fish …


Zoning And Complementary Incentives To Protect Farmland: A Case For Missoula County, Kaitlin Mccafferty Jan 2018

Zoning And Complementary Incentives To Protect Farmland: A Case For Missoula County, Kaitlin Mccafferty

Graduate Student Theses, Dissertations, & Professional Papers

Urban sprawl reflects an inefficient use of land that diminishes both rural landscapes and quality of life turning farms, ranches and open space into siloed suburban communities. This results in less walkable cities with more traffic and air pollution, among other negative consequences. Farmland constitutes a particularly important resource that often faces degradation or loss due to sprawl. Higher quality agricultural soils are particularly desirable for development because they are flat and well-drained. Farmland is also important for urban communities concerning food security, environmental health, and economic well being. As American cities continue to grow, farmland around urban areas has …


Investigating The Ecology Of A Rare Species On St. John, Usvi: Reintroducing Solanum Conocarpum In Light Of Climate Change, Cecilia Rogers Jan 2018

Investigating The Ecology Of A Rare Species On St. John, Usvi: Reintroducing Solanum Conocarpum In Light Of Climate Change, Cecilia Rogers

Senior Honors Projects, 2010-2019

Approximately two thirds of St. John is National Park territory. However, the land has been threatened with tourism and development, greatly impacting island biodiversity. One species that may become extinct due to this degradation is Solanum conocarpum. S. conocarpum is a rare shrub, endemic to the dry tropical forests of St. John, USVI. This plant is a species of conservation concern and is one of very few native and endemic plants on this island. Very little is known about the ecology and reproduction of S. conocarpum. Most plants are found on the southern half of the island. Recent observations …