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Effects of road management on movement and survival of Roosevelt elk Effects of road management on movement and survival of Roosevelt elk

Road closures frequently are used to manage for Rocky Mountain elk (Cervus elaphus nelsoni), but no studies have evaluated the effects of limited vehicle access on movements and survival of Roosevelt elk (C. elaphus roosevelti). We studied movements and survival of female Roosevelt elk before Road Management Areas (RMA) were designated, and during limited vehicular access from 1991 to...
Authors
Eric K. Cole, Michael D. Pope, Robert G. Anthony

Status and breeding ecology of the southwestern willow flycatcher in the Grand Canyon Status and breeding ecology of the southwestern willow flycatcher in the Grand Canyon

Ernpidonax trailIll extirnus is one of several recognized subspecies of the Willow Flycatcher (Unitt 1987, Browning 1993), a neotropical migrant that breeds across much of North America. This southwestern race is a riparian obligate, nesting in dense patches of willow (Salix sp.), willow-cottonwood (Populus sp.), or other similarly structured habitats. In some areas of the Southwest, it...
Authors
Mark K. Sogge, Timothy J. Tibbitts, Jim R. Petterson

Excavation of red squirrel middens by grizzly bears in the whitebark pine zone Excavation of red squirrel middens by grizzly bears in the whitebark pine zone

Whitebark pine seeds Pinus albicaulis are an important food of grizzly Ursus arctos horribilis bears wherever whitebark pine is abundant in the contiguous United States of America; availability of seeds affects the distribution of bears, and the level of conflict between bears and humans. Almost all of the seeds consumed by bears are excavated from middens where red squirrels...
Authors
D.J. Mattson, Daniel P. Reinhart

Photosynthesis of green algal soil crust lichens from arid lands in southern Utah, USA: Role of water content on light and temperature responses of CO2 exchange Photosynthesis of green algal soil crust lichens from arid lands in southern Utah, USA: Role of water content on light and temperature responses of CO2 exchange

Biotic soil crusts are a worldwide phenomenon in arid and semi-arid landscapes. Metabolic activity of the poikilohydric organisms found in these crusts is dominated by quick and drastic changes in moisture availability and long periods of drought. Under controlled conditions, we studied the role of water content on photosynthetic and respiratory CO2 exchange of three green algal soil...
Authors
Otto L. Lange, Jayne Belnap, Angelika Meyer

Why do international research and management? 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...
Authors
Todd K. Fuller, Mark R. Fuller, R.M. DeGraaf

Intestinal helminths of river otters (Lutra canadensis) from the Pacific Northwest Intestinal helminths of river otters (Lutra canadensis) from the Pacific Northwest

The intestinal helminth fauna of river otters, Lutra canadensis, from the Pacific Northwest was characterized by low species richness and intensity of infection. River otters from the lower Columbia River (n = 23) were infected with 9 species of helminths (83% prevalence); those from a relatively undisturbed reference area near the headwaters of the Trask and Wilson rivers on the Oregon...
Authors
Eric P. Hoberg, Charles J. Henny, O.R. Hedstrom, Robert A. Grove

Distribution of black-tailed jackrabbit habitat determined by GIS in southwestern Idaho 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...
Authors
Steven T. Knick, D.L. Dyer

Effects of drought and prolonged winter on Townsend's ground squirrel demography in shrubsteppe habitats Effects of drought and prolonged winter on Townsend's ground squirrel demography in shrubsteppe habitats

During a mark–recapture study of Townsend's ground squirrels (Spermophilus townsendii) on 20 sites in the Snake River Birds of Prey National Conservation Area, Idaho, in 1991 through 1994, 4407 animals were marked in 17639 capture events. This study of differences in population dynamics of Townsend's ground squirrels among habitats spanned a drought near the extreme of the 130-yr record...
Authors
Beatrice Van Horne, Gail S. Olson, Robert L. Schooley, Janelle G. Corn, Kenneth P. Burnham

Primary song by a juvenile willow flycatcher Primary song by a juvenile willow flycatcher

The timing of song development in suboscines, in which song appears not to be learned from other adults is poorly known. The Willow Flycatcher (Empidonax traillii) is a suboscine with a primary song typically referred to as fitz-bew. I report here an instance of very early singing by a 6-8-wk-old Willow Flycatcher, which sang in an aggressive context in response to a recording of adult...
Authors
M. K. Sogge

The role of sediment ingestion in exposing wood ducks to lead The role of sediment ingestion in exposing wood ducks to lead

Waterfowl on lateral lakes of the Coeur d'Alene River and on Lake Coeur d'Alene have been poisoned for many years by lead (Pb) from mining and smelting. In 1992 we undertook a study in the area to determine the importance of sediment ingestion in exposing wood ducks (Aix sponsa) to Pb. Digesta were removed from the intestines of wood ducks collected from contaminated and reference areas...
Authors
W. N. Beyer, L. J. Blus, Charles J. Henny, D. Audet
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