During the past decade (1978-87), breeding success and
productivity of bald eagles on the lower Columbia River (LCR) has
been far below state and regional averages and well below levels
required for delisting under the Endangered Species Act by the
Pacific States Bald Eagle Recovery Plan. Human disturbance was
suspected...
Since the early 1990s, declines in northern spotted owl (Strix occidentalis caurina) populations have been documented through extensive field surveys and range-wide demographic analyses. Although loss of late-successional forest has been credited as the primary cause for spotted owl population declines, environmental variation has also been shown to influence vital...
The California brown pelican (Pelecanus occidentalis californicus) is listed as an endangered species under the U.S. Endangered Species Act. The Recovery Plan for this subspecies outlines the need to "Assure long-term protection of adequate food supplies and essential. . .roosting. . . habitat throughout the range." I investigated the effects...
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,...
Few studies have evaluated non-migratory Roosevelt elk (Cervus elaphus roosevelti)
interactions and habitat use on lands undergoing extensive timber removal. We captured and
radio-tracked for 14 months representatives from 29 different bands of elk across a 37,000 ha area
of Oregon's Coast Range. We identified 6 habitat variables within individual...
I studied abundance patterns and habitat use of eight cavitynesting bird species in the Coast Ranges of Western Oregon during the
spring and summer of 1985 and 1986. Three age classes of unmanaged Douglas-fir (Pseudotsuga menziesii) stands were selected for study:
young (40-80 yrs), mature (80-200 yrs), and old-growth (>200...
The ecology of female Great Basin Canada geese (Branta
canadensis moffitti) and their broods was studied during the rearing
seasons of 1983 and 1984 on the Columbia River in southcentral
Washington. The movements and activities of 41 adult female geese,
marked with radio-transmitters, and their broods were monitored.
Adult female...
I investigated survival, movements, home range sizes, and habitat selection of pygmy rabbits (Brachylagus idahoensis) in southeastern Oregon and northwestern Nevada from June 2005 to June 2007. I trapped 298 rabbits on four sites and fitted each with radio transmitters. More than 13,000 locations of telemetered rabbits were recorded. I...