Publications
Filter Total Items: 2072
Interim Summary: Nesting Counts of Ospreys and Brown Pelicans in Northwestern Mexico, 2006 Interim Summary: Nesting Counts of Ospreys and Brown Pelicans in Northwestern Mexico, 2006
The distribution and abundance of nesting populations of California brown pelicans (Pelecanus occidentalis californicus) and ospreys (Pandion haliaetus) were documented in 2006 in northwestern Mexico. For ospreys only, the 2006 data were compared to population estimates from two previous surveys (one conducted in 1977 and another conducted in the period 1992-1993). Overall, the total...
Authors
Charles J. Henny, Daniel W. Anderson
Assessment and management of dead-wood habitat Assessment and management of dead-wood habitat
The Bureau of Land Management (BLM) is in the process of revising its resource management plans for six districts in western and southern Oregon as the result of the settlement of a lawsuit brought by the American Forest Resource Council. A range of management alternatives is being considered and evaluated including at least one that will minimize reserves on O&C lands. In order to...
Authors
Joan Hagar
Pygmy rabbit surveys on state lands in Oregon Pygmy rabbit surveys on state lands in Oregon
The pygmy rabbit (Brachylagus idahoensis) is classified by the federal government as a species of concern (i.e., under review by the U.S. Fish and Wildlife Service for consideration as a candidate for listing as threatened or endangered under the Endangered Species Act) because of its specialized habitat requirements and evidence of declining populations. The Oregon Department of Fish...
Authors
Joan Hagar, George Lienkaemper
Longitudinal patterns of fish assemblages, aquatic habitat, and water temperature in the Lower Crooked River, Oregon Longitudinal patterns of fish assemblages, aquatic habitat, and water temperature in the Lower Crooked River, Oregon
The Lower Crooked River is a remarkable groundwater-fed stream flowing through vertical basalt canyons in the Deschutes River Valley ecoregion in central Oregon (Pater and others, 1998). The 9-mile section of the river between the Crooked River National Grasslands boundary near Ogden Wayside and river mile (RM) 8 is protected under the National Wild and Scenic Rivers Act (16 U.S.C. 1271...
Authors
Christian E. Torgersen, David P. Hockman-Wert, Douglas S. Bateman, David W. Leer, Robert E. Gresswell
Fish movement ecology in high gradient headwater streams: Its relevance to fish passage restoration through stream culvert barriers Fish movement ecology in high gradient headwater streams: Its relevance to fish passage restoration through stream culvert barriers
Restoration of fish passage through culvert barriers has emerged as a major issue in the Pacific Northwest and nationwide, in part, because of their potential influence on fish movement. Movement is an essential mechanism by which mobile animals acquire the resources necessary for the successful completion of their life-cycles. In this report, we provide a brief review of some essential
Authors
Robert L. Hoffman, Jason B. Dunham
Rainforest birds: A land manager's guide to breeding bird habitat in young conifer forests in the Pacific Northwest Rainforest birds: A land manager's guide to breeding bird habitat in young conifer forests in the Pacific Northwest
This document (hereafter Guide) has been prepared to assist land managers interested in conducting conservation and management activities to benefit breeding birds associated with young conifer forests in the Pacific Northwest. Audiences targeted for use of the Guide include land trusts, watershed councils, non-commercial private land owners, forest products companies, land-managing...
Authors
Bob Altman, Joan Hagar
Marking techniques Marking techniques
No abstract available.
Authors
Daniel E. Varland, J.A. Smallwood, Leonard S. Young, Michael N. Kochert
Nutrient vectors and riparian processing: A review with special reference to African semiarid savanna ecosystems Nutrient vectors and riparian processing: A review with special reference to African semiarid savanna ecosystems
This review article describes vectors for nitrogen and phosphorus delivery to riparian zones in semiarid African savannas, the processing of nutrients in the riparian zone and the effect of disturbance on these processes. Semiarid savannas exhibit sharp seasonality, complex hillslope hydrology and high spatial heterogeneity, all of which ultimately impact nutrient fluxes between riparian...
Authors
Shayne M. Jacobs, J.S. Bechtold, Harry C. Biggs, N. B. Grimm, S. Lorentz, M.E. McClain, R.J. Naiman, Steven S. Perakis, G. Pinay, M.C. Scholes
Impacts of a gape limited Brook Trout, Salvelinus fontinalis, on larval Northwestern salamander, Ambystoma gracile, growth: A field enclosure experiment Impacts of a gape limited Brook Trout, Salvelinus fontinalis, on larval Northwestern salamander, Ambystoma gracile, growth: A field enclosure experiment
The formation of amphibian population structure is directly affected by predation. Although aquatic predators have been shown to have direct negative effects on larval salamanders in laboratory and field experiments, the potential impacts of gape-limited fish on larval salamander growth has been largely underexplored. We designed an enclosure experiment conducted in situ to quantify the...
Authors
C.R. Currens, W.J. Liss, R.L. Hoffman
Invasion by nonnative brook trout in Panther Creek, Idaho: Roles of local habitat quality, biotic resistance, and connectivity to source habitats Invasion by nonnative brook trout in Panther Creek, Idaho: Roles of local habitat quality, biotic resistance, and connectivity to source habitats
Theoretical models and empirical evidence suggest that the invasion of nonnative species in freshwaters is facilitated through the interaction of three factors: habitat quality, biotic resistance, and connectivity. We measured variables that represented each factor to determine which were associated with the occurrence of nonnative brook trout Salvelinus fontinalis in Panther Creek, a...
Authors
Joseph R. Benjamin, Jason B. Dunham, M.R. Dare
Long-term limnological research and monitoring at Crater Lake, Oregon Long-term limnological research and monitoring at Crater Lake, Oregon
Crater Lake is located in the caldera of Mount Mazama in Crater Lake National Park, Oregon. The lake has a surface area of about 53 km2at an elevation of 1882 m and a maximum depth of 594 m. Limited studies of this ultraoligotrophic lake conducted between 1896 and 1981, lead to a 10-year limnological study to evaluate any potential degradation of water quality. No long-term variations in...
Authors
G.L. Larson, R. Collier, M. Buktenica
Distribution of breeding shorebirds on the Arctic Coastal Plain of Alaska Distribution of breeding shorebirds on the Arctic Coastal Plain of Alaska
Available information on the distribution of breeding shorebirds across the Arctic Coastal Plain of Alaska is dated, fragmented, and limited in scope. Herein, we describe the distribution of 19 shorebird species from data gathered at 407 study plots between 1998 and 2004. This information was collected using a single-visit rapid area search technique during territory establishment and...
Authors
James A. Johnson, Richard B. Lanctot, Brad A. Andres, Jonathan Bart, Stephen C. Brown, Steven J. Kendall, David C. Payer