The U.S. Bureau of Fisheries (now National Marine Fisheries Service) conducted stream habitat surveys in the Upper Grande Ronde River Basin in 1941. This survey was part of an extensive inventory of stream habitat conditions for anadromous salmonids (Oncorhynchus spp.) throughout the Columbia River Basin. The survey systematically
inventoried 158...
One of the goals of ecosystem management is to integrate management of many species and processes across a range of temporal and spatial scales. I investigated the relationship between small mammals and amphibians at 3 spatial scales. My objective
was to identify, habitat associations of forest floor vertebrates at the...
Forest floor vertebrate species presence and abundance may be influenced by the volume and cover of coarse woody debris (CWD) in managed forests. I studied macro- and microhabitat associations of vertebrate species in 18 closed-canopy stands ranging in CWD volume from 14 to 859 m3/ha. Pitfall traps were used to...
The structure of a mature Douglas-fir (Pseudotsuga menziesii)
forest in a watershed in the western Cascades of Oregon was examined.
Two age classes were detected in the stand, the oldest originating
about 1855 after an extensive fire and the younger following a second
fire about 1895 Although the trees in...
Associations between occupancy patterns of a montane anuran species, Rana cascadae, and habitat structure at multiple scales were examined to investigate how population structure may influence persistence in spatially and temporally heterogeneous environments. Predictions were based on population dynamics suggested by source-sink and metapopulation models. Potential sites in three basins...
Management of habitat for bats requires sound information on their habitat requirements. I used radio telemetry to identify 80 roosts for 24 long-eared myotis (Myotis evotis); 74 roosts were identified for 21 females and 6 roosts for 3 males.
Females primarily used dead and defective conifer trees (n=22) and conifer...
Eight cougars were radio-collared and monitored during 1985 - 1987. Home range size, determined by minimum convex polygons, averaged 153.1 km2 for females, 543.5 km2 for males. Core home range size, determined by harmonic mean analysis, averaged 21.7 km2 for females, 17.9 km2 for males. Home ranges of males and...
To effectively manage for biodiversity at broad, ecosystem scales, the influences of habitat structure at multiple spatial scales on vertebrate species must be understood. There are few studies on the broad-scale habitat requirements of stream amphibians despite their importance in streams in forest ecosystems in the Pacific Northwest (PNW) as...
Vegetation provides food for many insects, and many insects serve as food for bats. We investigated the linkages among these three trophic levels in riparian areas throughout the Oregon Coast Range by examining the influence of vegetation cover, composition, and structure on the activity of nocturnal insects and bats, the...
Thinning has the potential to increase structural diversity of managed forests for wildlife. During 1994-1996, I conducted experimental and observational studies using pitfall trapping to assess short-term and potential long-term effects of thinning on abundance and reproduction of forest-floor vertebrates in Douglas-fir (Pseudotsuga menzeisii) forests of the Oregon Coast Range....