Publications
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Nitrogen metabolism of sheep and goats consuming Acacia brevispica and Sesbania sesban
We described the effects of two East African browses, Acacia brevispica and Sesbania sesban, on nitrogen metabolism of sheep and goats. The A. brevispica had a substantial amount of proanthocyanidins (condensed tannins); S. sesban did not. The browses were fed at three levels in combination with vetch (Vicia dasycarpa) and teff straw (Eragrostis abyssinica). Fecal N, N balance, and plasma urea N (
Authors
A. Woodward, J.D. Reed
Characteristics of nesting areas used by San Clemente Island Sage Sparrows
I examined the nest habitat used by Sage Sparrows (Amphispiza belli clementeae) on San Clemente Island, one of the California Channel Islands, during March through June 1986. All nests were found in boxthorn shrubs in coastal scrub habitat. The cover of vegetation was greater and more evenly distributed at nest sites than in surrounding habitat. Nests were placed most often on the leeward side of
Authors
David W. Willey
Reproduction of black-crowned night-herons related to predation and contaminants in Oregon and Washington, USA
We studied reproductive characteristics of Black-crowned Night-Herons (Nycticorax nycticorax) at four colonies in south central Washington and one colony in north central Oregon in 1991. Nest success, adjusted using the Mayfield method, was significantly different between colonies and ranged from 12-84% to hatching and 12-73% to 14 days post-hatching. The mean number of young surviving to 14 days
Authors
L. J. Blus, Barnett A. Rattner, M. J. Melancon, C. J. Henny
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. The av
Authors
W. N. Beyer, L. J. Blus, C. J. Henny, D. Audet
The scientific bases for preservation of the Mariana crow
The Panel recently released the report and recommendations resulting from its work over the last six months. Although primarily focused on the Mariana Crow, the report highlights that this is a matter potentially far more serious than the preservation of the crow on Guam and Rota. The report includes major sections dealing with the need to intensify research and control activities on the Brown T
Authors
Committee on the Scientific Bases for the Preservation of the Mariana Crow National Research Council, W.D. Duckworth, S. R. Beissinger, S.R. Derrickson, T. H. Fritts, S. M. Haig, F.C. James, J.M. Marsluff, B.A. Rideout
Selection of microsites by grizzly bears to excavate biscuitroots (Lomatium cous)
Roots of the biscuitroot (Lomatium cous) are a common food of grizzly bears (Ursus arctos horribilis) in drier parts of their southern range. I used random sampling and locations of radiomarked bears in the Yellowstone ecosystem to investigate the importance of mass and starch content of roots, digability of the site, and density of plants relative to selection of sites by grizzly bears to dig bis
Authors
D.J. Mattson
Gradients, vegetation and climate: spatial and temporal dynamics in the Olympic Mountains, USA
The steep environmental gradients of mountains result in the juxtaposition of diverse vegetation associations with narrow ecotones because life zones are compressed. Variation in geologic substrate, landforms, and soils, in combination with steep environmental gradients, create habitat diversity across spatial scales from 106 ha to <10 m2. This leads to higher biodiversity in a smaller space than
Authors
David L. Peterson, Edward G. Schreiner, Nelsa M. Buckingham
Population identification of western hemisphere shorebirds throughout the annual cycle
Identification of relationships among geographically distinct populations of migratory species can provide an understanding of breeding and natal philopatry, migration pathways, and population mixing during winter. We used random amplified polymorphic DNA (RAPD) analyses to search for markers specific to difficult‐to‐differentiate shorebird species (e.g. long‐billed dowitcher Limnodromus scolopace
Authors
Susan M. Haig, C. L. Gratto-Trevor, Thomas D. Mullins, M. A. Colwell
Effectiveness of artificial nesting structures for Ferruginous Hawks in Wyoming
No abstract available.
Authors
James R. Tigner, Mayo W. Call, Michael N. Kochert
Effects of silvicultultural modifications of temperate rainforest on breeding and wintering bird communities, Prince of Wales Island, southeast Alaska
We inventoried breeding and wintering bird communities in four treatments
of temperate rainforest on Prince of Wales Island, southeast Alaska during 1991-1992 and
1992-1993. The four forest treatments sampled included: (1) young growth (20 years) originating
from clearcut logging with no silvicultural modification (non-modified), (2) young
growth (20 years) precommercially thinned along unifor
Authors
Dominick A. Dellasala, Joan C. Hagar, Kathleen A. Engel, W.C. McComb, Randal L. Fairbanks, Ellen G. Campbell
Simulating secondary succession of elk forage values in a managed forest landscape, western Washington
Modern timber management practices often influence forage production for elk (Cervus elaphus) on broad temporal and spatial scales in forested landscapes. We incorporated site-specific information on postharvesting forest succession and forage characteristics in a simulation model to evaluate past and future influences of forest management practices on forage values for elk in a commercially manag
Authors
Kurt J. Jenkins, Edward E. Starkey
Can shrub cover increase predation risk for a desert rodent?
Previous research indicates that predation risk may influence activity patterns, habitat partitioning, and community structure of nocturnal desert rodents. Shrub microhabitat is typically considered safer than open microhabitat for these small mammals. We investigated predation risk for Townsend's ground squirrels (Spermophilus townsendii), which are diurnal desert rodents that detect predators vi
Authors
Robert L. Schooley, Peter B. Sharpe