Thesis (M.S.)--Oregon State University, 2007. / Printout. Includes bibliographical references (leaves 81-85). Also available on the World Wide Web.

Thesis (M.S.)--Oregon State University, 2001. / Typescript (photocopy). Includes bibliographical references (leaves 71-77). Also available online.

Thesis (M.Sc.). / Written for the Dept. of Natural Resource Sciences. Title from title page of PDF (viewed 2009/06/29). Includes bibliographical references.

Thesis (M.S.)--University of Montana, 2006. / Title from PDF t.p. (viewed on Feb. 26, 2007). Includes bibliographical references.

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The importance of spatial variation in abundance for the assessment of climate change impacts was examined using the North American beaver ( Castor canadensis) in Quebec as a model species. A preliminary characterization of the beavers' range edge improved the core-sampling bias and revealed that beavers are present at low densities, in shrubby riparian habitats as far north as the communities of Tasiujaq and Umiujaq. Spatial variation in beaver abundance across the province follows a roughly logistic pattern, with abundance peaking in southern Quebec, declining steeply around 49°N, and remaining uniformly low as far as 58°N. Although climate sensitivity of beaver abundance and the greatest changes in future beaver density are predicted to occur near the middle of their range, beavers are expected to occupy most of the province by 2055. These results highlight the value of incorporating density estimates from across a species' range into climate envelope models.

The American beaver, the largest rodent of North America, is distributed in ponds, lakes, and streams from Alaska to northern Mexico. This semi-aquatic mammal is considered an ecosystem engineer because beavers modify the landscape by cutting trees and by creating dams and ponds that have important effects on the aquatic community structure, providing habitat for aquatic invertebrates, fish, and birds. The American beaver has played an important socioeconomic role in the history of North America due to beavers' fur value, which caused the near extirpation of this mammal at the beginning of the 1900s due to overharvest by early Europeans. Because of the highly specific habitat requirements of beavers, this mammal also suffers the effects of habitat loss in some areas where riparian ecosystems are now scarce. My objectives in this study were to assess how climatic and geological events affected the current distribution of the American beaver in North America, and how the management actions to restore and control beaver populations have affected the genetic structure and conservation of beaver populations. Specifically, I addressed four aspects of the management and conservation genetics of the beaver: 1) a literature review of the management of beavers in the past 100 years; 2) the development of novel microsatellite DNA markers to address the population genetic structure aspects of the study; 3) the use of these microsatellite DNA markers to assess genetic diversity of current populations of beavers and to detect past population bottlenecks; and 4) the use of two mitochondrial DNA genes to resolve the current phylogeography of the American beaver in order to better understand how historical factors have affected the beaver's current distribution and genetic structure in North America. The results from this study provide information of the effects that management actions and climatic events can have on the genetic structure of beavers. This information can be used by wildlife biologists, and land managers, to develop future strategies for management and conservation of the American beaver.

The distribution of Lahontan cutthroat trout Oncorhynchus clarki henshawi was assessed in a high-desert stream in southeastern Oregon where beaver Castor canadensis are abundant. Longitudinal patterns of beaver ponds, habitat, temperature, and Lahontan cutthroat trout age group distribution were identified throughout Willow Creek. Three distinct stream segments were classified based on geomorphological characteristics. Four beaver-pond and four free-flowing sample sections were randomly located in each of the three stream segments. Beavers substantially altered the physical habitat of Willow Creek increasing the depth and width of available habitat. In contrast, there was no measurable effect on water temperature. The total number of Lahontan cutthroat trout per meter was significantly higher in beaver ponds than free-flowing sections. Although density (fish/m��) showed no statistically significant (P<0.05) increase, values in beaver ponds were two-fold those of free-flowing sections. Age-1 and young-of-the-year trout were absent or in very low numbers in lower Willow Creek because of elevated temperatures, but high numbers of age-2 and 3 (adults) Lahontan cutthroat trout were found in beaver ponds where water temperatures reached lethal levels (>24��C). Apparently survival is greater in beaver ponds than free-flowing sections as temperatures approach lethal limits. / Graduation date: 2003

This thesis explores patterns of faunal exploitation habits at the McDonald site, in the Saint-Anicet area during the Late Woodland period. The main goal is to determine the importance of wild game in the Iroquoian economical system which is based on the balance of fishing, hunting and horticulture. The result of the faunal analysis shows that White-Tailed Deer, North American Black Bear and North American Beaver are the most important taxa contributing to the subsistence economy of the inhabitants of the site. This was determined by standard zooarchaeological methods, including calculation of the number of identified specimens (NISP), the minimum number of individuals (MNI), meat weight (MW) and ethnohistorical data. This thesis also discusses the spatial distribution of animal skeletal remains, comparing meat consumption patterns within each family unity inside the longhouses and within and between each longhouse. This comparison shows that faunal remains are mostly located in the central alignment of longhouses and are homogeneously distributed. The taxa distributed within the longhouses suggest relatively equalitarian access to animal resources. Analysis of the bone concentrations shows a collaborative tendency between family units within the community. Furthermore, the faunal assemblage tends to show an annual occupation of the site. Sedentary occupation of the site is also supported by ceramic analysis and cultigen analysis. Finally, we compare the mammal NISP and MNI of the McDonald's site with seven other contemporaneous archaeological sites from the region. This comparison shows that mammalian resources declined in importance in the Iroquoian diet between the beginning of the 14th century and the first part of the 16th century, probably due to the adoption of horticulture. / Ce mémoire porte sur l'exploitation de la faune par les habitants du site McDonald de la région de Saint-Anicet. L'objectif principal est de caractériser la place des mammifères dans l’économie mixte des Iroquoiens du Saint-Laurent à un moment où l’horticulture gagne en popularité. L’étude de l’assemblage faunique a permis de déterminer que le cerf de Virginie, l’ours noir et le castor du Canada sont les principaux taxons mammaliens qui contribuent de façon économique, technologique et symbolique à l’économie de subsistance des habitants du site McDonald. Cette étude a été menée en intégrant des statistiques descriptives propres à la zooarchéologie telles que le nombre de restes déterminés (NRD), le nombre minimal d’individus (NMI) et le poids de viande (PV) avec des sources d’informations connexes telles que des documents ethnohistoriques, des guides fauniques et des statistiques gouvernementales. Ce travail utilise également l’analyse de la distribution spatiale des restes squelettiques qui montre une répartition des matières dures animales majoritairement alignée dans l’axe central des maisons-longues. La distribution spatiale des taxons montre quant à elle une homogénéité dans la dispersion des animaux entre les maisons-longues, ainsi qu’une répartition relativement égalitaire des ressources carnées entre les unités familiales. L’analyse des concentrations révèle même un esprit de collaboration entre les unités familiales contiguës. De plus, le spectre de faune tend à démontrer une occupation annuelle du site, ce qui corrobore l’analyse céramique et l’analyse des cultigènes. Finalement, en comparant le NRD et le NMI mammalien du site McDonald avec sept autres sites contemporains, l’analyse faunique démontre que les ressources mammaliennes sont en décroissance dans l’alimentation des Iroquoiens entre le début du 14e siècle et la première moitié du 16e siècle, période qui correspond justement à l’essor de l’horticulture (maïs, haricot, courge) au sein de la diète iroquoienne, ce qui caractérise l’économie mixte de la période du Sylvicole supérieur.