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Publications

Filter Total Items: 1994

Forest floor bryophytes of Pseudotsuga menziesii-Tsuga heterophylla stand in Oregon: Influences of substrate and overstory

Species richness and abundance of bryophytes inhabiting forest floor substrates were assessed at two sites in western Oregon. Bryophyte diversity, abundance, and community composition were compared between sites, and between young forest stands (~55 yrs) and old-growth stands (400 + yrs) within each site. Relationships of stand structural features to diversity and community composition were assess
Authors
T. Rambo, Patricia S. Muir

Monitoring species richness and abundance of shorebirds in the western Great Basin

Broad-scale avian surveys have been attempted within North America with mixed results. Arid regions, such as the Great Basin, are often poorly sampled because of the vastness of the region, inaccessibility of sites, and few ornithologists. In addition, extreme variability in wetland habitat conditions present special problems for conducting censuses of species inhabiting these areas. We examined t
Authors
Nils Warnock, Susan M. Haig, Lewis W. Oring

Winter foraging ecology of bald eagles on a regulated river in southwest Idaho

We studied Bald Eagle foraging ecology on the South Fork Boise River,Idaho, during the winters of 1990-92. We compared habitat variables at 29 foraging sites, 94 perch sites, and 131 random sites.Habitat variables included river habitat (pool, riffle, run), distance to the nearest change in river habitat, distance to nearest available perch, number and species of surrounding perches, and average
Authors
Gregory S. Kaltenecker, Karen Steenhof, Marc J. Bechard, James C. Munger

Short-term influence of tank tracks on vegetation and microphytic crusts in shrubsteppe habitat

Nutt.) habitat within the Idaho Army National Guard Orchard Training Area in southwestern Idaho. The purpose of this study was to determine the short-term (1–2 years) influence of tank tracks on vegetation and microphytic crusts in shrubsteppe habitat. The two types of tank tracks studied were divots (area where one track has been stopped or slowed to make a sharp turn) and straight-line tracks. D
Authors
Stephen E. Watts

Demographic and growth responses of a guerrilla and a phalanx perennial grass in competitive mixtures

The advantages of guerrilla and phalanx growth for the guerrilla Elymus lanceolatus ssp. lanceolatus and phalanx E. l. ssp. wawawaiensis were evaluated over 2 years in two taxon mixtures with a range of densities of each subspecies and under two levels of watering.Ramet numbers and biomass of the guerrilla subspecies were higher than those of the phalanx grass in the first year but in the second y
Authors
L. David Humphrey, David A. Pyke

Status of the white-faced ibis: Breeding colony dynamics of the Great Basin population, 1985-1997

The status of the White-faced Ibis (Plegadis chihi) in the Great Basin is of concern because of its small population size and the limited and dynamic nature of its breeding habitat. We analyzed existing annual survey data for the White-faced Ibis breeding in the Great Basin and surrounding area for 1985-1997. Methods varied among colonies and included flight-line counts and fixed-wing aircraft and
Authors
Susan L. Earnst, L. Neel, G.L. Ivey, T. Zimmerman

Limitations to mapping habitat use areas in changing landscapes using the Mahalanobis distance statistic

We tested the potential of a GIS mapping technique, using a resource selection model developed for black-tailed jackrabbits (Lepus californicus) and based on the Mahalanobis distance statistic, to track changes in shrubsteppe habitats in southwestern Idaho. If successful, the technique could be used to predict animal use areas, or those undergoing change, in different regions from the same selecti
Authors
Steven T. Knick, J.T. Rotenberry

Declining ring-necked pheasants in the Klamath Basin, California: I. Insecticide exposure

A study of organophosphorus (OP) insecticide exposure was conducted on a declining population of ring-necked pheasants (Phasianus colchicus) associated with agricultural lands at Tule Lake National Wildlife Refuge (TLNWR) during the summers of 1990–92. Findings at TLNWR were compared with a nearby pheasant population at Lower Klamath National Wildlife Refuge (LKNWR) not subjected to intensive farm
Authors
Robert A. Grove, D. R. Buhler, Charles J. Henny, A. D. Drew

Spatial distribution of breeding passerine bird habitats in a shrubsteppe region of southwestern Idaho

A paper describing the similarities and differences between trichomoniasis and pox infection. The need for laboratory diagnosis to differentiate between them is indicated.
Authors
Steven T. Knick, J.T. Rotenberry

Water relations of riparian plants from warm desert regions

Riparian plants have been classified as 'drought avoiders' due to their access to an abundant subsurface water supply. Recent water-relations research that tracks water sources of riparian plants using the stable isotopes of water suggests that many plants of the riparian zone use ground water rather than stream water, and not all riparian plants are obligate phreatophytes (dependent on ground wat
Authors
S.D. Smith, Dale A. Devitt, James R. Cleverly, David E. Busch