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Publications

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Gyrfalcon feeding behavior during the nestling period in central west Greenland Gyrfalcon feeding behavior during the nestling period in central west Greenland

We studied gyrfalcon (Falco rusticolus) food delivery and feeding behavior during the nestling period in central West Greenland during the 2000 and 2001 field seasons. We used time-lapse video cameras installed at three nests to record 2677.25 hours of nestling video. Ptarmigan delivered to nests were usually plucked prior to delivery and included the breast and superior thoracic...
Authors
Travis Booms, Mark R. Fuller

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

Habitat use by Swainson's Hawks on their austral winter grounds in Argentina Habitat use by Swainson's Hawks on their austral winter grounds in Argentina

We examined the use of agricultural habitats by Swainson's Hawks (Buteo swainsoni)in La Pampa and Santa Fe provinces, Argentina. We found an association of foraging Swainson's Hawks with permanent pastures such as fallow, natural, and alfalfa fields. The hawks also used plowed fields for sunning, resting, and preening. Fields planted with annual crops and pastures were used very little...
Authors
Sonia B. Canavelli, Marc J. Bechard, B. Woodbridge, Michael N. Kochert, Juan J. Maceda, Maria E. Zaccagnini

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

Estimating population trends with a linear model Estimating population trends with a linear model

We describe a simple and robust method for estimating trends in population size. The method may be used with Breeding Bird Survey data, aerial surveys, point counts, or any other program of repeated surveys at permanent locations. Surveys need not be made at each location during each survey period. The method differs from most existing methods in being design based, rather than model...
Authors
Jonathan Bart, Brian D. Collins, R. I. G. Morrison

Historical wetlands in Oregon's Willamette Valley: Implications for restoration of winter waterbird habitat Historical wetlands in Oregon's Willamette Valley: Implications for restoration of winter waterbird habitat

Before agricultural expansion in the 19th century, river valleys of North America supported expanses of wetland habitat. In restoring these landscapes, it is important to understand their historical condition and biological function. Synthesizing historical primary accounts (from explorers, travelers, settlers, and farmers) with contemporary knowledge of these wetland systems, we...
Authors
Oriane W. Taft, Susan M. Haig

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

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

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
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