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Competition between the Threatened Bliss Rapids Snail, Taylorconcha serpenticola (Hershler et al.) and the Invasive, Aquatic Snail, Potamopyrgus antipodarum (Gray): Author: Richards, David Charles; Date: 2004-12-15; Program: Biological Sciences; Abstract: Due primarily to habitat loss and invasive species, extinction rates for North American mollusk taxa are among the highest for any taxonomic group in the world. Competition between invasive and native species often leads to decreases in native populations. For example, a primary reason for listing the Bliss Rapids snail, Taylorconcha serpenticola as threatened in the Snake River drainage was the perceived impacts of the highly invasive New Zealand mudsnail, Potamopyrgus antipodarum. Despite federal protection of T. serpenticola and the known presence of P. antipodarum in the Snake River draina...; Download File | View full details

Conifer Cover Increase in the Greater Yellowstone Ecosystem: Rates, Extent, and Consequences for Carbon: Author: Powell, Scott Lael; Date: 2004-12-15; Program: Biological Sciences; Abstract: Increases in the extent and density of woody vegetation have been observed in many locations worldwide. Conifer cover increase in the Greater Yellowstone Ecosystem (GYE) has been documented by historical photos, but the rate and extent remain unquantified. Elevated atmospheric CO₂ levels have focused research attention on carbon budgeting. Carbon sinks associated with conifer cover increase are believed to account for a fraction of the "missing carbon sink," although estimates of the fraction are highly uncertain. I examined changes in conifer cover and aboveground carbon a...; Download File | View full details

Demography of Lewis's Woodpecker, Breeding Bird Densities, and Riparian Aspen Integrity in a Grazed Landscape: Author: Newlon, Karen Rachel; Date: 2005-05-15; Program: Biological Sciences; Abstract: Aspen (Populus tremuloides) riparian woodlands are extremely limited in distribution throughout the western U.S., yet these habitats have a disproportionate value to breeding birds. Aspen habitats are also considered prime sheep and cattle summer range, particularly in the semiarid Intermountain West. Such concentrated use has raised concern about the effects of sheep and cattle grazing on these habitats. We examined the influences of sheep and cattle grazing on aspen riparian woodlands and the associated breeding bird community. We had two objectives: 1) to determine how habitats grazed by sh...; Download File | View full details

Dynamics of the Waterborne Stage of Myxobolus Cerebralis Estimated Directly by Packed-Bed Filtration: Author: Lukins, Halcyon Josephine; Date: 2004-08-15; Program: Biological Sciences; Abstract: Past assessments of whirling disease infection risk on wild trout populations have relied on disease severity experienced by cultured fish exposed in sentinel cages or flatscreen filtration of Myxobolus cerebralis triactinomyxons. The former technique is indirect and inexpedient whereas the latter is imprecise and inaccurate. I examined spatial and temporal dynamics of Myxobolus cerebralis triactinomyxon concentrations directly using packed-bed filtration at five mainstem sites on the upper Madison River and at Willow Creek, a tributary to the Jefferson River. Packed-bed filtration provides ac...; Download File | View full details

Effects of Varying Habitats on Competition between Endangered San Joaquin Kit Foxes (Vulpes macrotis mutica) and Coyotes (Canis latrans): Author: Nelson, Julia Lynn; Date: 2005-12-15; Program: Biological Sciences; Abstract: Coyotes (Canis latrans) are the primary predator of endangered San Joaquin kit foxes (Vulpes macrotis mutica). Coyotes often associate with coverrich habitats while kit foxes use grasslands, alkali shrublands, and urban environments. Effects of varying habitats on coyote and kit fox competition are relatively unknown. I assessed exploitation and interference competition between coyotes and kit foxes in grassland and shrubland habitats to determine if kit foxes are niche displaced by coyotes. I evaluated habitat and spatial partitioning, diet, and prey abundance of kit foxes and coyotes, as wel...; Download File | View full details

Interactions between the Invasive New Zealand Mud Snail, Potamopyrgus antipodarum, Baetid Mayflies, and Fish Predators: Author: Cada, Chelsea Ann; Date: 2004-12-15; Program: Biological Sciences; Abstract: The nonindigenous gastropod Potamopyrgus antipodarum is quickly spreading through aquatic environments in the western United States, and populations often occur at very high densities. In previous studies, densities of baetid mayflies were lower in reaches with high densities of Potamopyrgus than in reaches with low densities of Potamopyrgus in Darlinton Spring Creek (Madison River drainage, Montana, USA), suggesting exploitation or interference competition. To determine when Potamopyrgus had the greatest effect on baetids, I quantified densities and biomasses of Potamopyrgus and baetids in lo...; Download File | View full details

Lichens and their Distribution in Lewis and Clark Caverns State Park: Author: Salix, Jessie Lynn; Date: 2004-05-15; Program: Biological Sciences; Abstract: Lichens are unique organisms composed of two to three different organisms living together in a symbiotic relationship. They occur in most terrestrial habitats and perform many valuable roles in an ecosystem. Many species of lichen are sensitive to airborne pollutants, making them good Biological indicators of air quality. A high diversity of lichens can indicate a relatively stable environment. In this study, an exhaustive inventory of the lichen species in Lewis and Clark Caverns State Park, Jefferson County, Montana, was done by collecting from all substrates in 22 different sites. The distr...; Download File | View full details

Recruitment Probabilities and Reproductive Costs for Weddell Seals in Erebus Bay, Antarctica: Author: Hadley, Gillian Louise; Date: 2006-05-15; Program: Biological Sciences; Abstract: The study of life history traits such as age at first reproduction and the evaluation of recruitment probabilities and reproductive costs allow insight regarding the diverse factors and mechanisms shaping reproductive strategies. We investigated these mechanisms using a 26-year mark-resight dataset for Weddell seals (Leptonychotes weddellii) in Erebus Bay, Antarctica. Mean age at first reproduction was 7.62 years of age (SD=1.71), but varied from four to 14 suggesting the presence of important heterogeneity in quality among females. Survival rate was maximized for offspring of age-14 mothers (...; Download File | View full details

Remote Sensing of Wetlands in Yellowstone National Park: Author: Wright, Christopher Kevin; Date: 2004-12-15; Program: Biological Sciences; Abstract: As part of the Amphibian Research and Monitoring Initiative, satellite remote sensing was used to identify potential wetland amphibian habitat in Yellowstone National Park. Landsat Thematic Mapper imagery was combined with ancillary predictors of wetland occurrence including habitat type, cover type, landform type, bedrock geology, soil attributes, terrain measures, and climate data. Classification trees were used to predict the likelihood of palustrine wetland occurrence across the Yellowstone landscape. Wetland maps generated by this study are intended to address shortcomings of the National...; Download File | View full details

Rural Residential Development in the Greater Yellowstone: Rates, Drivers, and Alternative Future Scenarios: Author: Hernandez, Patricia Cristina; Date: 2004-05-15; Program: Biological Sciences; Abstract: Rates of immigration and rural land use change in the American West have far exceeded the national average, and have been exceptionally rapid in the Greater Yellowstone Ecosystem. Because the Greater Yellowstone is ecologically unique, is still largely undeveloped, and is characterized by unrestrictive land use policies, it is a particularly relevant place to study past and potential future growth in rural residential development. The scientific approach used to investigate trends in rural residential development involved the both the testing of specific hypotheses regarding historical develop...; Download File | View full details

The Steller Sea Lion (Eumetopias jubatus) Decline and the Gulf of Alaska / Bering Sea Commercial Fishery: Author: Hennen, Daniel Reneau; Date: 2004-12-15; Program: Biological Sciences; Abstract: The Steller sea lion (SSL) population in Alaska was listed as threatened under the Endangered Species Act in 1991. Several procedural restrictions were placed on the commercial fisheries of the region at that time in an effort to reduce the potential for human induced mortality on sea lions. Several years have elapsed since these restrictions were put into place and questions about their efficacy abound. In an effort to determine whether or not fisheries interventions have helped the SSL population to recover, estimates of the fishing activity of the Bering Sea/ Gulf of Alaska commercial fishe...; Download File | View full details

Use of Satellite Imagery to Measure Cover of Prairie Vegetation for the Detection of Change: Author: Hurst, Rebecca Jeanne; Date: 2006-05-15; Program: Biological Sciences; Abstract: Adaptive resource management requires a cost effective, easily repeatable tool for measurement of vegetation quality and comparison of management treatment effects across a natural area and through time. High-resolution satellite imagery may be used as a guide for treatment by facilitating either the comparison of differentially treated units or the measurement of change in vegetation through time. Demonstration of successful application of remote sensing for measurement of vegetation to recognize trends in vegetation quality will help adaptive managers both to apply and to improve the methods...; Download File | View full details

Behavioral Ecology of the Striped Hyena (Hyaena hyaena): Author: Wagner, Aaron Parker; Date: 2006-05-15; Program: Biological Sciences; Abstract: Relatedness is often estimated from microsatellite genotypes that include null alleles (Dakin & Avise 2004). When null alleles are present, observed genotypes represent one of several possible true genotypes. If null alleles are detected, but analyses do not adjust for their presence (i.e., observed genotypes are treated as true genotypes), then estimates of relatedness and relationship can be incorrect. The number of loci available in many wildlife studies is limited, and loci with null alleles are commonly a large proportion of data that cannot be discarded without substantial loss of po...; Download File | View full details

Riparian Vegetation of the Montana Yellowstone and Cattle Grazing Impacts Thereon: Author: Eggers, Margaret Joy Slack; Date: 2005-12-15; Program: Biological Sciences; Abstract: The objects of my research were two. To describe ungrazed vegetation of thirty sites well dispersed along the 500 mile length of the Yellowstone River. And to measure the effects of gazing on this vegetation by describing/comparing vegetation of these ungrazed control sites with the vegetation of nearby grazed sites. Vegetation of the Yellowstone consists of three lateral bands on open shore (gravel or sandbar), willow thicket, and cottonwood forest. Their appearance on successively older deposits suggests control both by decreasing water availability (greater depth to water on inland sites wi...; Download File | View full details

The Role of Rodents as a Potential Reservoir for Pasteurella multocida on the National Elk Refuge, Wyoming: Author: Swanekamp, Leatrice June; Date: 2005-05-15; Program: Biological Sciences; Abstract: Hemorrhagic septicemia (HS) is a fatal disease affecting domestic and wild ruminants caused by the bacterium Pasteurella multocida. Although uncommon in the U.S, outbreaks of HS in elk (Cervus elaphus) occurred on the National Elk Refuge (NER) in the winters of 1986, 1987, 1993, 1995, 1999, and 2001. DNA fingerprinting of P. multocida from the 1987 and 1993 outbreaks (B:3,4 HhaI 036/HpaII 001) revealed the same organism was responsible for mortality in both years. However, testing has failed to find this genetic variant in healthy elk on the NER, suggesting reservoirs other than elk might play...; Download File | View full details

Age Structure, Growth, and Factors Affecting Relative Abundance of Life History Forms of Bull Trout in the Clark Fork River Drainage, Montana and Idaho: Author: Zymonas, Nikolas Dainus; Date: 2006-12-15; Program: Biological Sciences; Abstract: Bull trout Salvelinus confluentus exhibit high variability in life history patterns. Better understanding of the underlying mechanisms is needed to assist conservation efforts. I assessed relationships among life history form, growth rates, age structures, and environmental variables, using pelvic fin rays and scales to estimate age and growth. First, I assessed the effects of pelvic fin ray excision on survival and growth of age-3 and age-4 bull trout. Survival and growth were similar between fin ray-excised and control fish within each age group, although a bacterial coldwater disease infect...; Download File | View full details

Expression Profiling and Function Elucidation of Anaplastic Lymphoma Kinase in the Developing Nervous System: Author: Hurley, Shawn Patrick; Date: 2006-05-15; Program: Biological Sciences; Abstract: During embryonic development, complex events such as cellular proliferation, differentiation, survival, and guidance of axons are orchestrated and regulated by a variety of extracellular signals. Receptor tyrosine kinases mediate many of these events with several playing critical roles in neuronal survival and axonal guidance. It is evident that not all the receptor tyrosine kinases that play key roles in regulating neuronal development have been identified. In these studies, we have characterized the spatial-temporal expression profile of a recently identified receptor tyrosine kinase, anapla...; Download File | View full details

Behavioral Responses of Elk (Cervus elaphus) to the Threat of Wolf (Canus lupus) Predation: Author: Winnie, John Arthur, Jr.; Date: 2006-05-15; Program: Biological Sciences; Abstract: We studied individual and herd level behavioral responses of elk to spatial and temporal variation in the risk of predation by wolves over three winters in the Upper Gallatin drainage, Montana. Within a given drainage, elk of both sexes moved into or closer to protective cover (timber) in response to wolf presence. Cow elk responded to elevated risk by increasing vigilance in exchange for foraging, and large mixed (cow, calf, spike) herds substantially decreased in size. In contrast, when wolves were present, bulls did not increase vigilance levels, nor decrease feeding, and small bull-only gr...; Download File | View full details

Alpine and Cliff Ecosystems in the North-Central Rocky Mountains: Author: Aho, Ken Andrew; Date: 2006-08-15; Program: Biological Sciences; Abstract: Data collection and analysis for managed wild lands is vital to their effective stewardship. To address this I gathered and analyzed data for largely undocumented alpine and cliff ecosystems located in the North-Central Rocky Mountains. This information should aid in decision-making processes for regional land managers and increase the overall ecological understanding of these systems. This manuscript includes detailed community analyses of alpine vegetation and its environment on andesitic-volcanic substrates in the Washburn Range and the Northern Absarokas. It also places the Washburn Range...; Download File | View full details

A Genomic Screen for Zic1 Target Genes in Neural Development: Author: Li, Shuzhao; Date: 2006-08-15; Program: Biological Sciences; Abstract: The transcription factor Zic1 plays important roles in patterning the neural plate in early vertebrate development. A crucial step toward understanding the mechanisms of Zic1 function is to identify the downstream target genes. We misexpressed Zic1 in animal caps from Xenopus embryos, and screened for differential gene expression with DNA microarrays. Candidate genes from these microarray data were further validated by quantitative PCR. Through this study, eleven genes have been shown to be directly upregulated by Zic1. One of the direct targets of Zic1 is a novel gene that we have named Xfeb....; Download File | View full details

An Analysis of Whirling Disease Risk in Western Montana: Author: McGinnis, Stephanie Ann; Date: 2007-05-15; Program: Biological Sciences; Abstract: Myxobolus cerebralis, the causative agent of whirling disease, has been a major contributor to the loss of young trout in numerous streams within the Intermountain West (Colorado, Idaho, Montana, Utah, Wyoming). Currently there are no effective management procedures for mitigating the effects of this disease because it is not fully known why the parasite has severe effects in some trout populations while remaining fairly benign in others. Characteristics of the parasite, hosts, environment, and their interactions, may partially explain varying responses of wild rainbow trout populations to whi...; Download File | View full details

Myxospore Detection in Soil and Angler Movement in Southwestern Montana: Implications for Whirling Disease Transport: Author: Gates, Kiza Kristine; Date: 2007-05-15; Program: Biological Sciences; Abstract: Movement of anglers among rivers in southwestern Montana presents a potential pathway for the spread of whirling disease and other aquatic nuisance species (ANS) on soil laden angling equipment. The objectives of this study were to 1) determine the effectiveness of a density extraction to isolate myxospores from soil and the effectiveness of polymerase chain reaction (PCR) at detecting M. cerebralis myxospores in soil; 2) quantify movement of resident and non-resident anglers in southwestern Montana and soil quantity carried on angling equipment; and 3) determine myxospore adherence to wading ...; Download File | View full details

Survival Rate Estimates of Florida Manatees (Trichechus manatus latirostris) Using Carcass Recovery Data: Author: Schwarz, Lisa Kimberley; Date: 2007-12-15; Program: Biological Sciences; Abstract: The Florida manatee (Trichechus manatus latirostris) is classified as an endangered species and is also protected under the Marine Mammal Protection Act. The manatees' coastal distribution coincides with areas of high human density, making manatees particularly vulnerable to human impacts. Important management decisions on both the state and federal level rely heavily on extinction models that require estimates of survival and reproductive rates. Current mark-recapture methods are unable to estimate survival rates for younger age classes because many young manatees lack the unique scarring us...; Download File | View full details

Nest-Site Selection and Nest Survival of Two Woodpecker Species in Ponderosa-Pine Dominated Forests: Author: Story, Scott Joseph; Date: 2007-12-15; Program: Biological Sciences; Abstract: Management of woodpecker populations requires knowledge of nesting habitat and vital rates in different forest conditions. We examined nest-site selection and nest survival for two woodpeckers, northern flicker (Colaptes auratus) and hairy woodpecker (Picoides villosus) at three locations in ponderosa-pine forests of the interior Columbia River Basin. Our goals were to: (1) characterize the range of habitat conditions available to nesting woodpeckers in our study area; (2) determine which habitat features best discriminated between nest and non-nest plots, and (3) establish which habitat featu...; Download File | View full details

Effects of Acclimation on Poststocking Dispersal of Age-1 Pallid Sturgeon: Author: Oldenburg, Eric William; Date: 2008-05-15; Program: Biological Sciences; Abstract: A propagation program for pallid sturgeon Scaphirhynchus albus in the upper Missouri River was implemented by the U. S. Fish and Wildlife Service in 1997. Preliminary research indicated that many hatchery-reared pallid sturgeon were experiencing significant downstream poststocking dispersal, negatively affecting their recruitment. Therefore, the objective of this study was to evaluate the effects of acclimation to flow and site-specific physicochemical water conditions on poststocking dispersal and physiological condition of age-1 pallid sturgeon. Fish from three acclimation treatments were ra...; Download File | View full details

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