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Publications

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Habitat segregation of Ambystoma gracile and Ambystoma macrodactylum in mountain ponds, Mount Rainer National Park, Washington, USA Habitat segregation of Ambystoma gracile and Ambystoma macrodactylum in mountain ponds, Mount Rainer National Park, Washington, USA

Ambystoma gracile (Baird) and Ambystoma macrodactylum Baird are common salamander species occupying key trophic positions in mountain ponds and lakes of Mount Rainier National Park (MORA). Based on amphibian surveys conducted in ponds and lakes in the northeast quadrant of MORA during the summers of 1993a??1995, 20 sites were resampled in 1996 to document and evaluate distributions of...
Authors
Robert L. Hoffman, Gary L. Larson, Brendan J. Brokes

Time-lapse video sysem used to study nesting Gyrfalcons Time-lapse video sysem used to study nesting Gyrfalcons

We used solar-powered time-lapse video photography to document nesting Gyrfalcon (Falco rusticolus) food habits in central West Greenland from May to July in 2000 and 2001. We collected 2677.25 h of videotape from three nests, representing 94, 87, and 49% of the nestling period at each nest. The video recorded 921 deliveries of 832 prey items. We placed 95% of the items into prey...
Authors
Travis Booms, Mark R. Fuller

Measurements of thermal updraft intensity over complex terrain using American white pelicans and a simple boundary-layer forecast model Measurements of thermal updraft intensity over complex terrain using American white pelicans and a simple boundary-layer forecast model

An examination of boundary-layer meteorological and avian aerodynamic theories suggests that soaring birds can be used to measure the magnitude of vertical air motions within the boundary layer. These theories are applied to obtain mixed-layer normalized thermal updraft intensity over both flat and complex terrain from the climb rates of soaring American white pelicans and from...
Authors
H.D. Shannon, G.S. Young, M. Yates, Mark R. Fuller, W. Seegar

Response of birds to thinning young Douglas-fir forests Response of birds to thinning young Douglas-fir forests

As a result of recent fire history and decades of even-aged forest management, many coniferous forests in western Oregon are composed of young (20-50 yrs), densely stocked Douglas-fir stands. Often these stands are structurally simple - a single canopy layer with one or two overstory tree species - and have a relatively sparse understory. The lack of structural complexity in these stands...
Authors
John P. Hayes, Jennifer M. Weikel, Manuela M. P. Huso, Janet L. Erickson

Protocol for determining bull trout presence Protocol for determining bull trout presence

The Western Division of the American Fisheries Society was requested to develop protocols for determining presence/absence and potential habitat suitability for bull trout. The general approach adopted is similar to the process for the marbled murrelet, whereby interim guidelines are initially used, and the protocols are subsequently refined as data are collected. Current data were
Authors
James Peterson, Jason B. Dunham, Philip Howell, Russell Thurow, Scott Bonar

Assessing rangelands Assessing rangelands

It is important for land managers and technical assistance specialists to be able to assess the health of rangelands in order to know where to focus management efforts. The complexity of ecological processes, and the inherent expense of directly measuring site integrity, suggests a need for an evaluation process that focuses instead on biological and physical attributes. In a...
Authors
David A. Pyke

Space use, migratory connectivity, and population segregation among Willets breeding in the western Great Basin Space use, migratory connectivity, and population segregation among Willets breeding in the western Great Basin

Western Willets (Catoptrophorus semipalmatus inornatus) were banded (n = 146 breeding adults and chicks) and radio-marked (n = 68 adults) at three western Great Basin wetland complexes to determine inter- and intraseasonal space use and movement patterns (primarily in 1998 and 1999). Birds were then tracked to overwintering sites where migratory connectivity and local movements were...
Authors
S. M. Haig, L.W. Oring, P.M. Sanzenbacher, O.W. Taft

Golden eagles in the U.S. and Canada: Status, trends, and conservation challenges Golden eagles in the U.S. and Canada: Status, trends, and conservation challenges

We reviewed the literature to assess status and population trends and to identify mortality factors affecting Golden Eagle populations in the U.S. and Canada. Nesting populations in Alaska and Canada are stable, but some nesting populations in the western U.S. have declined. Small but steady declines in the intermountain West have been associated with shrub loss and declining jackrabbit
Authors
Michael N. Kochert, Karen Steenhof

Abundances of northwestern salamander larvae in montane lakes with and without fish, Mount Rainier National Park, Washington Abundances of northwestern salamander larvae in montane lakes with and without fish, Mount Rainier National Park, Washington

In Mount Rainier National Park, the northwestern salamander usually inhabits relatively large and deep lakes and ponds (average size = 0.3 ha; average depth > 2 m) that contain flocculent, organic bottom sediments and abundant coarse wood. Prior to 1970, salmonids were introduced into many of the park's lakes and ponds that were typical habitat of the northwestern salamander. The...
Authors
Gary L. Larson, Robert L. Hoffman

Space use, migratory connectivity, and population segregation among willets breeding in the western Great Basin Space use, migratory connectivity, and population segregation among willets breeding in the western Great Basin

Western Willets (Catoptrophorus semipalmatus inornatus) were banded (n = 146 breeding adults and chicks) and radio-marked (n = 68 adults) at three western Great Basin wetland complexes to determine inter- and intraseasonal space use and movement patterns (primarily in 1998 and 1999). Birds were then tracked to overwintering sites where migratory connectivity and local movements were...
Authors
Susan M. Haig, Lewis W. Oring, Peter M. Sanzenbacher, Oriane W. Taft

Nitrogen loss from nonpolluted South American forests mainly via dissolved organic compounds Nitrogen loss from nonpolluted South American forests mainly via dissolved organic compounds

Conceptual1,2,3,4 and numerical5,6,7,8 models of nitrogen cycling in temperate forests assume that nitrogen is lost from these ecosystems predominantly by way of inorganic forms, such as nitrate and ammonium ions. Of these, nitrate is thought to be particularly mobile, being responsible for nitrogen loss to deep soil and stream waters. But human activities—such as fossil fuel combustion
Authors
Steven S. Perakis, L. O. Hedin
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