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Publications

Filter Total Items: 1990

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

A comparison of small-mammal communities in a desert riparian floodplain

We compared small-mammal communities between inactive floodplain and actively flooded terraces of riparian habitat in the Verde Valley of central Arizona. We used species diversity, abundance, weight of adult males, number of juveniles, number of reproductively active individuals, longevity, residency status, and patterns of microhabitat use to compare the two communities. Although abundances of s
Authors
Laura E. Ellison, Charles van Riper

Factors influencing the distribution and abundance of diaptomid copepods in high elevation lakes in the Pacific Northwest, USA

We investigated the impact of abiotic factors and trout density on distribution and abundance of diaptomid copepods in high-elevation lakes in North Cascades National Park Service Complex (NOCA), Washington, USA. The most common large diaptomid, D. kenai (mean length = 1.88 mm), was able to persist over a wide range of abiotic factors, but the small herbivorous diaptomid, D. tyrrelli (mean length
Authors
W.J. Liss, Gary L. Larson, E. Deimling, L. Ganio, Robert L. Hoffman, G.A. Lomnicky

Mitigation of habitat "take" and the core area concept

No abstract available.
Authors
J. Buchanan, R.J. Fredrickson, D.E. Seaman

Winter range expansion by the northern Yellowstone elk herd

Your next big-game bag may be a record breaker -- so check it against the 21 weight charts given by these expert technicians.
Authors
Thomas O. Lemke, J.A. Mack