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Publications

Filter Total Items: 1999

The influence of habitat, prey abundance, sex, and breeding success on the ranging behavior of Prairie Falcons

We studied the ranging behavior and habitat selection of radio-tagged Prairie Falcons (Falco mexicanus) during the breeding season in southwestern Idaho. The distribution and numbers of Townsend's ground squirrels (Spermophilus townsendii), the primary prey of Prairie Falcons in our study area, varied in response to drought during the study period. Prairie Falcons ranged over large areas (ca. 300
Authors
J.M. Marzluff, Bryan A. Kimsey, Linda S. Schueck, Mary E. McFadzen, M.S. Vekasy, James C. Bednarz

Why do international research and management?

The pheasant, in its North American range, seems to have had its greatest success in glaciated or in other areas associated with calcareous soils. Success has been slight in areas deficient in calcium.....In Lancaster County, Pennsylvania, no environmental difference other than presence or absence of limestone was discovered that might explain the high population in the limestone valley and the sc
Authors
Todd K. Fuller, Mark R. Fuller, R.M. DeGraaf

Use of burrow entrances to indicate densities of Townsend's ground squirrels

Counts of burrow entrances have been positively correlated with densities of semi-fossorial rodents and used as an index of densities. We evaluated their effectiveness in indexing densities of Townsend's ground squirrels (Spermophilus townsendii) in the Snake River Birds of Prey National Conservation Area (SRBOPNCA), Idaho, by comparing burrow entrance densities to densities of ground squirrels es
Authors
Beatrice Van Horne, Robert L. Schooley, Steven T. Knick, G.S. Olson, K.P. Burnham

Landscape characteristics of disturbed shrubsteppe habitats in southwestern Idaho (USA)

We compared 5 zones in shrubsteppe habitats of southwestern Idaho to determine the effect of differing disturbance combinations on landscapes that once shared historically similar disturbance regimes. The primary consequence of agriculture, wildfires, and extensive fires ignited by the military during training activities was loss of native shrubs from the landscape. Agriculture created large squar
Authors
Steven T. Knick, J.T. Rotenberry

Spatial use and habitat selection of golden eagles in southwestern Idaho

We measured spatial use and habitat selection of radio-tagged Golden Eagles (Aquila chrysaetos) at eight to nine territories each year from 1992 to 1994 in the Snake River Birds of Prey National Conservation Area. Use of space did not vary between years or sexes, but did vary among seasons (home ranges and travel distances were larger during the nonbreeding than during the breeding season) and amo
Authors
J.M. Marzluff, Steven T. Knick, M.S. Vekasy, Linda S. Schueck, T.J. Zarriello

Distribution of black-tailed jackrabbit habitat determined by GIS in southwestern Idaho

We developed a multivariate description of black-tailed jackrabbit (Lepus californicus) habitat associations from Geographical Information Systems (GIS) signatures surrounding known jackrabbit locations in the Snake River Birds of Prey National Conservation Area (NCA), in southwestern Idaho. Habitat associations were determined for characteristics within a 1-km radius (approx home range size) of j
Authors
Steven T. Knick, D.L. Dyer

Double brooding by American kestrels in Idaho

No abstract available.
Authors
Karen Steenhof, B.E. Peterson

Interactive effects of prey and weather on golden eagle reproduction

1. The reproduction of the golden eagle Aquila chrysaetos was studied in southwestern Idaho for 23 years, and the relationship between eagle reproduction and jackrabbit Lepus californicus abundance, weather factors, and their interactions, was modelled using general linear models. Backward elimination procedures were used to arrive at parsimonious models.2. The number of golden eagle pairs occupyi
Authors
Karen Steenhof, Michael N. Kochert, T. L. McDonald

Clonal foraging in perennial wheatgrasses: A strategy for exploiting patchy soil nutrients

1. Foraging by means of plasticity in placement of tillers in response to low- and high-nutrient patches was examined in the rhizomatous wheatgrass Elymus lanceolatus ssp. lanceolatus. Its ability to exploit soil nutrient patches was compared to that of the closely related but caespitose E. lanceolatus ssp. wawawaiensis.2. Clones of 14 genets of each taxon were planted in boxes consisting of two 3
Authors
L. David Humphrey, David A. Pyke

Methods for evaluating crown area profiles of forest stands

Canopy architectures of five structurally complex forest stands and three structurally simple forest stands in southwest Oregon and the Willamette Valley, Oregon, were evaluated and quantified through crown area profiles. Mixed conifer and mixed conifer hardwood stands across a range of sites were sampled for crown widths and heights. Crown width and shape equations were derived and used to quanti
Authors
Michael E. Dubrasich, D.W. Hann, J. C. Tappeiner

Use of artificially created douglas-fir snags by cavity-nesting birds

In western Oregon, we created snags by sawing tops off live Douglas-fir (Pseudotsuga menziesii) (n = 821) trees and monitored their condition and use by cavity-nesting birds. We created snags in three silvicultural treatments: modified clearcut stands, two-story stands, and small-patch group-selection stands. We used two snag patterns: clumped and scattered. Created snags averaged 3.8/ha in densit
Authors
C. L. Chambers, T. Carrigan, T.E. Sabin, J. C. Tappeiner, W.C. McComb
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