I used program CAPTURE to analyze 1,535 data sets for 33 North American species of small mammals for sources of variation in capture probabilities and to characterize species-specific responses to markrecapture trapping. CAPTURE incorporates seven models to account for all possible combinations of heterogeneity (h), behavioral response (b), and time...
I studied small-mammal communities and their response to grazing in mixed-conifer forests and oak woodlands in the Cascade-Siskiyou National Monument in southern Oregon. My objectives were to (1) compare small-mammal communities among forest types and grazing intensities, (2) identify riparian affiliated species, and (3) describe microhabitat associations. Over two years,...
Earth’s mantle extends to nearly 3000 km depth, comprises >80 % of Earth’s total volume, and has the largest influence on the primordial and radiogenic heat budget. Despite its importance, the structure and composition of the mantle is still debated. There are three primary models for Earth’s mantle structure that...
As part of investigations to evaluate the suitability of sheep grazing in Douglas-fir (Pseudotsuga menziesii) plantations of Oregon's Coast Range, this research was designed to evaluate the effectiveness of sheep grazing in suppressing unwanted vegetation, determine seasonal variations in forage quality, and investigate the impact of sheep grazing on big...
Despite the belief that fuels management, a form of prescribed fire that reduces accumulated fuels in commercially thinned forests, is necessary to restore forest 'health' in the Pacific Northwest, its effects on wildlife has received little attention in the scientific literature. Because fuels management is supported, funded, and implemented nationwide...
Research was conducted on the Keating rangelands in north-eastern Oregon to determine the food habits of deer and cattle and
similarity of their diets, and to estimate deer and cattle months of
grazing on both a quantitative and nutritional basis. Data were
collected during the winters of 1978-1979, 1979-1980 and...
Denali National Park and Preserve (Denali) contains one of the highest densities of nesting Golden Eagles (Aquila cluysaetos) in North America. Productivity of this migratory population varies both temporally and spatially. Regardless of prey abundance, more fledglings are consistently produced at some nesting territories than others. In many raptor studies,...
The volcanic origin of the Samoan archipelago can be explained by one of three models, specifically, by a hot spot forming over a mantle plume, by lithospheric extension resulting from complex subduction tectonics in the region, or by a combination of these two processes, either acting sequentially or synchronously. In...