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Best Management Practices For The Conservation Of Western Pond Turtle Populations In California, Cristina Yarnal Dec 2019

Best Management Practices For The Conservation Of Western Pond Turtle Populations In California, Cristina Yarnal

Master's Projects and Capstones

This project provides insight into western pond turtle (Actinemys marmorata) population health at sites in three states on the western part of the United States. Washington, Oregon and California have identified the western pond turtle as endangered, a critical and a species of special concern in that respective order. Washington has implemented a recovery plan for western pond turtles and Oregon has established best management practices for the conservation of native turtles. California has yet to establish any guidelines for the conservation of western pond turtles. This species is endemic to the western United States and has been …


Ecology And Conservation Of Immature Sea Turtles Across Multiple Scales, Lucas Griffin Oct 2019

Ecology And Conservation Of Immature Sea Turtles Across Multiple Scales, Lucas Griffin

Doctoral Dissertations

Considering many sea turtle populations are a fraction of their historic size and anthropogenic threats within the marine environment are increasing, additional data are imperative to help mitigate anthropogenic disturbances and to build resilience into sea turtle populations. In this dissertation, I present three data chapters focused on immature sea turtle ecology and conservation. These chapters evaluate sea turtle ecology and conservation at varying scales, ranging from mitigating human-wildlife interactions at the individual level, to coastal movements and space use at the ecosystem level, and to large scale climate change impacts at the population level. Ultimately, these chapters provide a …


Geographic Population Structure And Taxonomic Identity Of Rhinichthys Osculus, The Santa Ana Speckled Dace, As Elucidated By Nuclear Dna Intron Sequencing, Liane Raynette Greaver Sep 2019

Geographic Population Structure And Taxonomic Identity Of Rhinichthys Osculus, The Santa Ana Speckled Dace, As Elucidated By Nuclear Dna Intron Sequencing, Liane Raynette Greaver

Electronic Theses, Projects, and Dissertations

Rhinichthys osculus (Cyprinidae), the speckled dace, is the most widely distributed freshwater fish in the western United States. The southern California populations of R. osculus are identified as the Santa Ana speckled dace (SASD), though the SASD has not yet been formally recognized as a distinct taxon. Current mtDNA analysis performed in the Metcalf Lab has shown a reciprocally monophyletic relationship among three California regions; southern, central coast, and Owens Valley. Similarly, microsatellite genotyping has shown significant levels of geographic population structure. The purpose of this study was to provide nuclear DNA sequence data to determine the taxonomic status of …


Rescue And Reestablishment Of Chicken Models For Spontaneously Occurring Hashimoto’S Thyroiditis And Systemic Sclerosis/Scleroderma, Joseph Zolton Hiltz Aug 2019

Rescue And Reestablishment Of Chicken Models For Spontaneously Occurring Hashimoto’S Thyroiditis And Systemic Sclerosis/Scleroderma, Joseph Zolton Hiltz

Graduate Theses and Dissertations

The loss of biodiversity is a topic gaining popularity both in the political and scientific forums. Nearly 30 years ago researchers and politicians congregated in Rio de Janeiro (1992) to attend the first Earth Summit. It was the first meeting of its kind discussing the tangible pressing consequences of biodiversity loss as well as the potential long term ramifications. Many of the countries represented at this summit implemented short and long term plans in order to accurately measure losses of biodiversity as well as establishing organizations to help diagnose and remedy the current problems at hand. These new organizations and …


Application Of Semi-Hydrophobic Layers To Decrease Bare Soil Evaporation, Jesse Lee Barnes Aug 2019

Application Of Semi-Hydrophobic Layers To Decrease Bare Soil Evaporation, Jesse Lee Barnes

UNLV Theses, Dissertations, Professional Papers, and Capstones

Evaporative water loss from bare agricultural soils is a primary area of water conservation research. Mulching is the commonly utilized method to decrease evaporative water loss. The most commonly utilized mulch is nonbiodegradable polyethylene sheeting because it tends to decrease evaporative water loss and increase crop yields more than environmentally friendly mulches. This study aimed to test the utility of sand coated with polymerized soybean oil (i.e., hydrophobic sand) as a treatment to reduce bare soil evaporation and an alternative to current practices. Evaporation rates were measured in laboratory soil columns containing both treated and untreated soils. Treatment parameters were …


Mixing It Up: The Impact Of Episodic Introgression On The Evolution Of High-Latitude Mesocarnivores, Jocelyn P. Colella Jul 2019

Mixing It Up: The Impact Of Episodic Introgression On The Evolution Of High-Latitude Mesocarnivores, Jocelyn P. Colella

Biology ETDs

At high latitudes, climatic oscillations have triggered repeated episodes of organismal divergence by geographically isolating populations. For terrestrial species, extended isolation in glacial refugia – ice-free regions that enable terrestrial species persistence through glacial maxima – is hypothesized to stimulate allopatric divergence. Alternatively, upon glacial recession, divergent populations expanded from independent glacial refugia and often contacted other diverging populations. In the absence of reproductive isolating mechanisms, this biogeographic process may trigger hybridization and ultimately, gene flow between divergent taxa. My dissertation research aims to understand how these episodic periods of isolation and contact have impacted the evolution of high latitude …


Factors Affecting Nest Success Of Colonial Nesting Waterbirds In Southwest Louisiana, Karis A. Ritenour Jul 2019

Factors Affecting Nest Success Of Colonial Nesting Waterbirds In Southwest Louisiana, Karis A. Ritenour

LSU Master's Theses

As the coastline of Louisiana shifts with global climate change, subsidence, and accelerated sea level rise, important breeding islands for colonial nesting waterbirds are disappearing. In many recent studies flooding has been a leading cause of nest failure for a variety of species, especially those that nest on the ground. I examined the nest success of four species of colonial nesting waterbirds with various nesting strategies on Rabbit Island in southwestern Louisiana during 2017 and2018 by determining nest and fledging success. I monitored 855 nests, including 457 Brown Pelicans nests with an estimated hatch probability of 70%, 270 Forster’s Terns …


The Effects Of Electrofishing On Different Life Stages Of Ozark And Eastern Hellbenders, Stephanie Kay Morrison May 2019

The Effects Of Electrofishing On Different Life Stages Of Ozark And Eastern Hellbenders, Stephanie Kay Morrison

MSU Graduate Theses

Electrofishing, a common method of freshwater fish sampling, has been shown to negatively affect some fish species, but the effects on non-target species, such as hellbenders, have not been well studied. I tested effects of electrofishing on the behavior of several life stages of captivereared Ozark (Cryptobranchus alleganiensis bishopi) and eastern (C. a. alleganiensis) hellbenders. Ozark hellbender eggs were exposed to different voltages in the laboratory, and embryos in higher voltages had higher incidences of twitching during exposures and higher numbers of morphological deformities after exposures. For hatchling Ozark hellbenders, which typically are sedentary, individuals moved more during exposure to …


Observation Of Visitors At A Chimpanzee (Pan Troglodytes Schweinfurthii) Ecotourism Site Reveals Opportunity For Multiple Modes Of Pathogen Transmission, Darcey Glasser May 2019

Observation Of Visitors At A Chimpanzee (Pan Troglodytes Schweinfurthii) Ecotourism Site Reveals Opportunity For Multiple Modes Of Pathogen Transmission, Darcey Glasser

Theses and Dissertations

Chimpanzee (Pan troglodytes) tracking is a popular ecotourism activity across Sub-Saharan Africa, offering visitors a personal wildlife experience. However, chimpanzee ecotourism may increase the risk of disease transmission between chimpanzees and people. This study assessed how tourist behaviors might facilitate cross-species disease transmission in Kibale National Park, Uganda.


Assessing Populations Of Eastern Brook Trout (Salvelinus Fontinalis) Above And Below Waterfalls In Mountain Streams Of Virginia, Hannah Eisemann Macmillan May 2019

Assessing Populations Of Eastern Brook Trout (Salvelinus Fontinalis) Above And Below Waterfalls In Mountain Streams Of Virginia, Hannah Eisemann Macmillan

Masters Theses, 2010-2019

Anthropogenically driven factors, such as increasing temperature and sediment in valley streams, acidification of mountain streams, and the introduction of non-native trout, are restricting habitat suitable for healthy populations of eastern brook trout (Salvelinus fontinalis) throughout their native Appalachian range. Brook trout are important as predators of insects in mountain streams and as a favorite of anglers. It is crucial that remaining populations in sustainable habitats be identified and preserved. Waterfalls are geologic knickpoints preventing base-level lowering that create unique, stable landscapes above them, which may alleviate the temperature-productivity/acidity “habitat squeeze” for populations of brook trout and could …


Herpetological Assemblages In Tropical Dry Forests Of The Azuero Peninsula, Panama: An Evaluation Of Reforestation, Tyler Kovacs May 2019

Herpetological Assemblages In Tropical Dry Forests Of The Azuero Peninsula, Panama: An Evaluation Of Reforestation, Tyler Kovacs

Masters Theses, 2010-2019

Tropical dry forests are considered one of the most endangered tropical ecosystems making reforestation increasingly necessary to restore Panama’s unique ecoregion. The isolated dry ecoregion surrounding the Bay of Parita in Panama has a long history of deforestation and cattle grazing. Successful reforestation of this land is important to restore ecosystem health and biodiversity. In Panama, reforestation ranges from monocultures of exotic teak (Tectona grandis) to passive regeneration. Faunal recovery within these reforestation systems may vary due to different habitat characteristics. In this study, amphibian and reptile communities were compared in two types of reforestation systems and protected riparian forests …


Biogeography Of Endemic Dragonflies Of The Ozark-Ouachita Interior Highlands, Wade Alexander Boys May 2019

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 …


Ontogeny Of Similarity And Disparity In Length-At-Age Of Coral Reef Fishes In The Family Acanthuridae Between Marine Protected And Fished Areas, Mathias Tjarko Cramer May 2019

Ontogeny Of Similarity And Disparity In Length-At-Age Of Coral Reef Fishes In The Family Acanthuridae Between Marine Protected And Fished Areas, Mathias Tjarko Cramer

Theses and Dissertations

Drastic reductions in the harvestable biomass of exploited fish populations on coral reefs and other marine coastal ecosystems have been hypothesized to be a consequence of astronomical and unrelenting fishing pressures, particularly in the coastal small-scale and sustenance fisheries of the world. It has recently been proposed that the causal relationship between fishing pressure and fish biomass is rooted in the negative effects of size-selective fishing mortality, which consequently instigates directional shifts in phenotype (i.e., fishing induced evolution). To mitigate the effects of unsustainable fishing pressures, parcels of traditional fishing grounds have been designated as Marine Protected Areas (MPAs). To …


Reassessment Of The Extinction Risk Of The Neotropical Freshwater Crabs Of The Family Pseudothelphusidae, Ada Acevedo Alonso May 2019

Reassessment Of The Extinction Risk Of The Neotropical Freshwater Crabs Of The Family Pseudothelphusidae, Ada Acevedo Alonso

All NMU Master's Theses

The Neotropical region is one of the world’s biodiversity hotspots, and its freshwater crabs are notably diverse, and are represented by two families, Pseudothelphusidae and Trichodactylidae. This study focuses on this region’s highly diverse Pseudothelphusidae which includes 48 genera and 289 species. The 2008 IUCN global conservation assessment found 15.5% of the Pseudothelphusidae to be threatened with extinction and projected that in the worst-case scenario (if all of the Data Deficient species turned out to be threatened), the number of threatened species would be significantly higher. In the last decade several new species of pseudothelphusids have been described, and more …


Exploration Of The Uae Native Plants For Sustainable Landscaping In Arid Region, Mubarak Mohammed S. R. Jaber Al Khaili Apr 2019

Exploration Of The Uae Native Plants For Sustainable Landscaping In Arid Region, Mubarak Mohammed S. R. Jaber Al Khaili

Philosophy Dissertations

In order to maintain sustainability for landscapes in the arid region, the use of native plants is of considerable importance, in the light of the fact that the exotic plants currently used do not resource efficient. The native plants adapted to the harsh environment of the desert ecosystem could play a critical role in this direction where the natural resources could be sustainably used. Research on evaluation and analyzes of native plant species of the UAE for potential application in landscapes have been considered. The present investigation reports the results of the exploration of native plants suited for sustainable landscape …


Population Viability And Connectivity Of The Federally Threatened Eastern Indigo Snake In Central Peninsular Florida, Javan Bauder Mar 2019

Population Viability And Connectivity Of The Federally Threatened Eastern Indigo Snake In Central Peninsular Florida, Javan Bauder

Doctoral Dissertations

Understanding the factors influencing the likelihood of persistence of real-world populations requires both an accurate understanding of the traits and behaviors of individuals within those populations (e.g., movement, habitat selection, survival, fecundity, dispersal) but also an understanding of how those traits and behaviors are influenced by landscape features. The federally threatened eastern indigo snake (EIS, Drymarchon couperi) has declined throughout its range primarily due to anthropogenically-induced habitat loss and fragmentation making spatially-explicit assessments of population viability and connectivity essential for understanding its current status and directing future conservation efforts. The primary goal of my dissertation was to understand how …


Integrating The Effects Of Biotic Interactions Into Models Of Species Distributions, Jamie M. Kass Feb 2019

Integrating The Effects Of Biotic Interactions Into Models Of Species Distributions, Jamie M. Kass

Dissertations, Theses, and Capstone Projects

The study of species geographic distributions and their environmental drivers has developed at a fast pace in recent years, owing to improvements in technology and data availability, and is increasingly relevant in this era of advancing global change. Currently, the field focuses heavily on a variety of techniques to statistically estimate species’ ranges I refer to collectively as species distribution models (SDMs). These models are now used across a wide range of disciplines, but inadequacies remain in implementation, methodology, and theory that are in need of new insight. In this thesis I will address two key shortcomings that require improvement …


Evaluation Of Range-Wide Occupancy And Survey Methods For The Giant Kangaroo Rat (Dipodomys Ingens), Alyssa E. Semerdjian Jan 2019

Evaluation Of Range-Wide Occupancy And Survey Methods For The Giant Kangaroo Rat (Dipodomys Ingens), Alyssa E. Semerdjian

Cal Poly Humboldt theses and projects

Though habitat suitability and occupancy are often correlated, they cannot always be inferred from each other. Therefore, a solid understanding of both is essential to effectively manage species. Recent studies have assessed range-wide habitat suitability for the giant kangaroo rat (Dipodomys ingens; GKR), but data regarding occupancy is lacking in parts of its distribution. Satellite and aerial imagery were used to identify GKR burrows across their known range, producing a range-wide occupancy map and non-invasive survey methods including track plates, manned flight, unmanned aerial vehicle, and sign surveys were conducted to determine effective methods for monitoring GKR occupancy. …


Diversification In The Neotropics – Evolution And Population Genetics Of The Armored Catfish Hypancistrus Sp. From The Xingu River, Marcella Goncalves Santos Jan 2019

Diversification In The Neotropics – Evolution And Population Genetics Of The Armored Catfish Hypancistrus Sp. From The Xingu River, Marcella Goncalves Santos

Electronic Theses and Dissertations

The Xingu River, one of the largest tributaries of the Amazon River, is currently in peril due to the recent construction of hydroelectric dams, but little is known about the numerous fish species it supports. This dissertation focuses on three pleco catfish species belonging to the genus Hypancistrus from the Xingu River with partially overlapping distributions: H. zebra, H. sp. (L174), and H. sp. (L66/333). Chapter 1 is a bibliographic review of Amazonian freshwater fish diversity, with the goal of discussing the hypotheses of speciation mechanisms that can be tested in this system, including the relative importance of ecological adaptation …


Cisco Science: Using Omics To Answer A Range Of Key Questions, Hannah Lachance Jan 2019

Cisco Science: Using Omics To Answer A Range Of Key Questions, Hannah Lachance

Graduate College Dissertations and Theses

Coregonines, including cisco (Coregonus artedi), kiyi (Coregonus kiyi), and bloater (Coregonus hoyi), are a focus for prey fish conservation and restoration efforts throughout the Laurentian Great Lakes. However, fundamental questions about coregonine ecology and genetics remain. For example, we know little about how the early life stages of coregonines respond to environmental change at either the genotypic or phenotypic level. We also have limited knowledge about how to identify different species at the larval stage and the genetic relationships among species, which makes the different species difficult to study at the larval stage. To increase the probability for success in …


Examining The Role Of Reproductive Interference In The Decline Of Native Green Treefrogs Following Cuban Treefrog Invasions, Joseph Kennedy Jan 2019

Examining The Role Of Reproductive Interference In The Decline Of Native Green Treefrogs Following Cuban Treefrog Invasions, Joseph Kennedy

Electronic Theses and Dissertations

Reproductive interference occurs when the mating behaviors of one species negatively impact the fitness of another species. It is of increasing interest in invasive species biology because the introduction of alien species often leads to novel sexual interactions with native taxa, which can contribute to their decline. I examined whether reproductive interference plays a role in the decline of native green treefrogs (Hyla cinerea) following invasions of Cuban treefrogs (Osteopilus septentrionalis) in the southeastern United States. The impetus for this study revolves around similarities in spectro-temporal features of Cuban treefrog courtship calls and green treefrog aggressive calls. The significance of …


Competition Or Facilitation: Examination Of Interactions Between Endangered Sida Hermaphrodita And Invasive Phragmites Australis, Samantha N. Mulholland Jan 2019

Competition Or Facilitation: Examination Of Interactions Between Endangered Sida Hermaphrodita And Invasive Phragmites Australis, Samantha N. Mulholland

Theses and Dissertations (Comprehensive)

Virginia Mallow (Sida hermaphrodita) is a perennial herb of the Malvaceae family that is native to riparian habitats in northeastern North America. Throughout most of its geographical distribution however, it is considered threatened and only two populations are known from Canada. The biology and ecology of S. hermaphrodita are still poorly understood and although few studies have been performed to determine the factors that contribute to the species rarity, it is considered threatened potentially due to the loss of habitat caused by exotic European Common reed (Phragmites australis subsp. australis) invasion. Allelopathic and phytotoxic conditioning of …


Using Lidar To Approximate Keystone Structure And Evaluate Management Practices In Potential Habitats Of The Endangered Karner Blue Butterfly (Lycaeides Melissa Samuelis), Brandyn Balch Jan 2019

Using Lidar To Approximate Keystone Structure And Evaluate Management Practices In Potential Habitats Of The Endangered Karner Blue Butterfly (Lycaeides Melissa Samuelis), Brandyn Balch

Graduate Theses, Dissertations, and Problem Reports

Keystone structure is the spatial structure required by a given species, at a scale that is determined by that species’ needs and mobility. The endangered Karner blue butterfly (Lycaeides melissa samuelis, hereafter KBB) has a keystone structure that incorporates trees and bushes to provide the mixture of sun and shade required to fulfil its life functions. Airborne light detection and ranging (lidar) is a potentially invaluable tool for characterizing keystone structures. However, lidar has yet to be utilized to evaluate structural suitability of KBB habitats. Therefore, I investigated the use of lidar for characterizing critical attributes of KBB habitat structure, …