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Publications

Filter Total Items: 1978

Influence of basin-scale physical variables on life history characteristics of cutthroat trout in Yellowstone Lake

Individual spawning populations of Yellowstone cutthroat trout Oncorhynchus clarki bouvieri differ in life history characteristics associated with broad spatial and temporal environmental patterns, but relationships between specific life history characteristics of Yellowstone cutthroat trout and physical aspects of the environment are poorly understood. We examined basin-scale physical characteris
Authors
Robert E. Gresswell, W.J. Liss, Gary L. Larson, P. J. Bartlein

Wilderness-dependent wildlife: The large and carnivorous

Wilderness is vital to the conservation of wildlife species that are prone to conflict with humans and vulnerable to human-caused mortality. These species tend to be large and are often carnivorous. Such animals are typically problematic for humans because they kill livestock and, occasionally, humans, and cause inordinate damage to crops. The vulnerability of large herbivores and carnivores to hu
Authors
David J. Mattson

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 Tamiasciurus hudsonic
Authors
D.J. Mattson, Daniel P. Reinhart

Use of lodgepole pine cover types by Yellowstone grizzly bears

Lodgepole pine (Pinus contorta) forests are a large and dynamic part of grizzly bear (Ursus arctos) habitat in the Yellowstone ecosystem. Research in other areas suggests that grizzly bears select for young open forest stands, especially for grazing and feeding on berries. Management guidelines accordingly recommend timber harvest as a technique for improving habitat in areas potentially dominated
Authors
D.J. Mattson

Clarification of effects of DDE on shell thickness, size, mass, and shape of avian eggs

Moriarty et al. (1986) used field data to conclude that DDE decreased the size or altered the shape of avian eggs; therefore, they postulated that decreased eggshell thickness was a secondary effect because, as a general rule, thickness and egg size are positively correlated. To further test this relationship, the present authors analyzed data from eggs of captive American kestrels. Falco sparveri
Authors
Lawrence J. Blus, Stanley N. Wiemeyer, Christine M. Bunck

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

Modelling root reinforcement in shallow forest soils

A hypothesis used to explain the relationship between timber harvesting and landslides is that tree roots add mechanical support to soil, thus increasing soil strength. Upon harvest, the tree roots decay which reduces soil strength and increases the risk of management -induced landslides. The technical literature does not adequately support this hypothesis. Soil strength values attributed to root
Authors
Arne E. Skaugset