Life Sciences Commons^™

Phenology Of The Invasive Balsam Woolly Adelgid, Adelges Piceae (Ratz.) (Hemiptera: Adelgidae), On Subalpine Fir In Northern Utah, Elizabeth L. Rideout

All Graduate Theses and Dissertations, Fall 2023 to Present

Balsam woolly adelgid (BWA) is an invasive true fir pest in North America. Native to Europe, BWA was first discovered in Utah attacking subalpine fir in 2017. Recent BWA-caused subalpine fir mortality in northern Utah has prompted the need for baseline biological research to support pest management. Small-bodied and blending easily with its environment, BWA is a challenging pest to detect and study. Phenology, or the timing and characteristics of life stages through the year, of BWA varies depending on elevation and climate and is unstudied in Utah. This research focuses on defining aspects of BWA’s phenology, including the number …

Fractally Sampling Diversity-Environment Relationships To Understand Plant Assemblage Health Across Spatial Scales, Elizabeth G. Simpson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Humans influence the health of ecosystems and rely on healthy ecosystems to support their livelihoods and well-being. By looking at how the parts of ecosystems interact we can understand and improve ecosystem health. Ecosystem interactions change across spatial scales or different size patches of area. For example, individual organisms interact with each other at small spatial scales, while at large spatial scales, communities of organisms interact with weather conditions. However, many research studies do not look at how ecosystem interactions change across spatial scales. To address this gap in ecological research, I use a fractal sampling design which samples at …

Avian Species Distribution Models: Using Location Data To Inform Management Decisions, Marilyn E. Wright

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Both state and federal wildlife agencies strive to conserve and protect wildlife and their habitats as an important public resource. Applied management decisions often rely on being able to obtain data that can efficiently and effectively enhance the understanding of these systems for informing management actions. Wildlife managers often focus efforts on a small subset of species from an ecosystem, typically called focal species, who can serve as surrogates for understanding the health and function of the system. Models that consider how these focal species interact with the ecosystem are often used to better understand important aspects of their life …

Population Demography, Spatial Ecology, And Habitat Use Of The Florida Box Turtle (Terrapene Bauri) On A Barrier Island, Michael D. Mills

USF Tampa Graduate Theses and Dissertations

Turtles are one the most threatened vertebrate groups in the world due to anthropogenic threats such as habitat loss and overexploitation. In addition to occupying a range that has been vulnerable to major habitat loss, the Florida box turtle (Terrapene bauri) is particularly at risk of overexploitation due to its popularity in the pet trade. Sanibel Island is a barrier island in southwest Florida that has experienced major habitat loss and is the site of a recent poaching event. In response to these threats, studies of both the population demography and spatial ecology were conducted on Sanibel’s Florida box turtle …

Joint Management Of Upland & Aquatic Habitat For The California Red-Legged Frog & California Tiger Salamander, Kyle E. Verblaauw

Master's Projects and Capstones

As federally and state protected amphibians, the California tiger salamander (Ambystoma californiense) and the California red-legged frog (Rana draytonii) are recipients of ample management focus. Both species face a variety of threats, including habitat loss and alteration, introduction of non-native species, spread of disease, and effects of climate change. While management plans for the California tiger salamander and California red-legged frog exist, they frequently do not consider both species in tandem and often contain multiple shortcomings. This document aims to address the shortfalls of current management by providing practical recommendations for jointly managing the upland and …

Individual Variability In Foraging Success Of Harbor Seals (Phoca Vitulina) Preying On Pacific Salmon (Oncorhynchus Spp.) Informs Predator Management, Grace Freeman

WWU Graduate School Collection

The complexities of trophic dynamics complicate the management of predator populations. In some cases, targeted culling campaigns are meant to control predator populations. In these campaigns, predators are considered ‘rogue individuals’ based on visitation rates to a site. This definition carries the underlying assumption that all predators impact prey equally, however, individual variability in foraging success may compromise such an assumption. Thus, to test the hypothesis that foraging success varies among individual predators, I studied harbor seals preying on adult Pacific Salmon during the 2014-2019 fall salmon runs. I analyzed individual harbor seal visitation rate and foraging success based on …

Pismo Clams (Tivela Stultorum) In Califorina: Population Status, Habitat Associations, Reproduction, And Growth, Alexandria R. Marquardt

Master's Theses

Marine shellfish play a vital role in intertidal ecosystems and coastal communities, but many of these fisheries are small-scale and lack the necessary monitoring to ensure long-term sustainability. Effective management often requires information on key demographic parameters, such as population status, reproduction and growth. Pismo clams (Tivela stultorum) are a culturally important and iconic species in California, which supported a thriving commercial and recreational fishery throughout much of the 1900’s. However, Pismo clam populations have declined statewide in recent decades and are attributed to human harvest and predation by California sea otters (Enhydra lutris); However, no …

Assessment Of Invasive Gypsophila Paniculata Control Methods In The Northwest Michigan Dunes, Emma K. Rice

Masters Theses

Gypsophila paniculata is an invasive species in Michigan’s northern lower peninsula and a problem invasive in much of the northern United States and Canada. Gypsophila paniculata readily outcompetes native plants in sandy, well-drained soils due to its deep taproot, which allows access to scarce resources. It reproduces and disperses mainly by seed, but the phenology of seed maturation is poorly understood. Gypsophila paniculata is of particular concern in lakeshore dunes because the areas where it is most dense are also populated by several endemic and threatened species. Despite many years of intensive management, high densities of G. paniculata persist …

Natural And Anthropogenic Drivers Of Tree Evolutionary Dynamics, Brandon M. Lind

Theses and Dissertations

Species of trees inhabit diverse and heterogeneous environments, and often play important ecological roles in such communities. As a result of their vast ecological breadth, trees have become adapted to various environmental pressures. In this dissertation I examine various environmental factors that drive evolutionary dynamics in threePinusspecies in California and Nevada, USA. In chapter two, I assess the role of management influence of thinning, fire, and their interaction on fine-scale gene flow within fire-suppressed populations of Pinus lambertiana, a historically dominant and ecologically important member of mixed-conifer forests of the Sierra Nevada, California. Here, I find evidence …

Importance Of Forest Structure For Amphibian Occupancy In North-Central Florida: Comparisons Of Naturally Regenerated Forests With Planted Pine Stands, Christopher J E Haggerty

USF Tampa Graduate Theses and Dissertations

Once dominant, longleaf pine forests of the southeastern United States have been modified by 97 percent, resulting in several animal species being listed as endangered and threatened. Pine plantation silviculture (tree plantings) now occupies half of the original longleaf range where several animal species of conservation concern have experienced recent local population declines. In North America, the accepted practice of pine plantations is to plant pines densely in rows for wood production. Given that land use is considered a primary local driver for the 30% of amphibian species currently at risk of extinction, and planted pine is predicted to expand …

Spatio-Temporal Factors Affecting Human-Black Bear Interactions In Great Smoky Mountains National Park, Nathan Buckhout

Masters Theses

Wildlife managers use models to aid in predicting high risk areas for human and black bear (Ursus americanus) interactions (HBI). These tools help managers implement management strategies to minimize HBI. Over 3,000 incidents of HBI were compiled from management reports at Great Smoky Mountains National Park (GSMNP) during 1998-2011, a park with 9-10.2 million visitors per year and a black bear population of about 1,600 bears.

We used data from bear management reports along with annual visitor use, mast and bear abundance data to develop a series of generalized linear models to assess the spatial and temporal factors …

Factors Influencing Nest Site Selection By Wood Turtles (Glyptemys Insculpta) In An Altered Forest Landscape, Ellery Ruther

Theses & Honors Papers

There have been many studies concerning wood turtle (Glyptemys insculpta) nest site selection, including studies that evaluate nest site conditions when stream sand banks are not available. However, because of the unique landscape at our study site (high gradient, first order streams) and rapidly diminishing wood turtle populations in Virginia, I am evaluating wood turtle nest site selection. Nine physiographic and vegetative characteristics from nest, positive, negative-one and negative-two control locations were evaluated using binomial generalized linear models and then best fit models were chosen using Akaike's Information Criterion (AIC). It was found that in lieu of typical stream …

Social Organization And Decision Making In North American Bison: Implications For Management, Ryan A. Shaw

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Social organization varies widely among herbivores, and the level of social organization in bison is widely debated. I hypothesized that when mother-daughter relationships are allowed to develop, bison form long-term associations. In my study, 25 treatment mothers were selected from a free-ranging herd and kept together with their calves, while 25 control females had their calves forcefully removed. Treatment mothers and offspring had by far the greatest number of associations with a greater percentage of individuals with a half weight index (HWI) > 0.50. The strongest associations (HWI > 0.31) were among treatment mothers and their offspring. Moreover, these associations persisted over …

Species And Habitat Interactions Of The Gopher Tortoise: A Keystone Species?, Christopher Catano

Electronic Theses and Dissertations

Species-species and species-habitat interactions have been demonstrated to be important in influencing diversity across a variety of ecosystems. Despite generalities in the importance of these interactions, appropriate mechanisms to explain them are absent in many systems. In sandhill systems of the southeast U.S., gopher tortoises have been hypothesized to be a crucial species in the maintenance of diversity and function. However, the mechanisms and magnitude in which they influence their communities and habitats have rarely been empirically quantified. I examined how habitat structure influences tortoise abandonment of burrows and how tortoise densities influence nonvolant vertebrate community diversity. Tortoise burrow abandonment …

Breeding Habitat Structure And Use By Kansas-Occurring Black Rail, Stephanie A. Kane

Master's Theses

Two subspecies of Black Rail Laterallus jamaicenis occur in the United States, and neither has been studied extensively. Of the two, the Eastern subspecies L. j. jamaicenis has a larger range, but has been studied to a lesser degree than the California subspecies (L. j. coturniculus Eastern Black Rail are known to breed at several locations in Kansas, but as in other inland populations, precisely where these individuals overwinter is unknown. Additionally, little information is available on characteristics of breeding habitat for inland Eastern Black Rail populations, and few studies have investigated the effect of habitat management techniques on these …

Efficacy Of Constructed Wetlands Of Various Depths For Natural Amphibian Community Conservation, Andrea Nicole Drayer

Online Theses and Dissertations

Wetlands provide critical habitat for a diverse group of amphibians and provide important ecosystem functions and services to humans. Despite this, most natural wetlands have been lost to land use practices. Consequently, constructing wetlands has become a common practice to mitigate for removed wetlands and to manage for wildlife. There were three primary objectives of this research: 1) to examine whether or not constructed wetlands located on ridge tops in eastern Kentucky in the Daniel Boone National Forest (DBNF) had amphibian communities comparable to natural ephemeral wetlands, 2) to examine amphibian predator-prey relationships within the constructed wetlands, and 3) to …

Application Of Electrified Fladry To Decrease Risk Of Livestock Depredation By Wolves (Canis Lupus), Nathan J. Lance

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Wolf (Canis lupus) predation on livestock can cause economic and emotional hardships for livestock producers, complicating the balance of wolf conservation with other human interests. New management tools that decrease risk of predation may offer additional flexibility or efficiency for both livestock producers and management agencies. I examined 1) the efficacy of electrified fladry compared to fladry at protecting a food source from wolves in captivity, 2) the efficacy of electrified fladry for reducing wolf use of pastures and preventing depredations, and 3) the applicability of electrified-fladry. In captivity I tested the reaction from 15 groups (46 wolves) …