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Genetics Show Current Decline and Pleistocene Expansion in Northern Spotted Owls Genetics Show Current Decline and Pleistocene Expansion in Northern Spotted Owls

The northern spotted owl (Strix occidentalis caurina) is one of the most controversial threatened subspecies ever listed under the U.S. Endangered Species Act. Because of concern for persistence of the subspecies, logging on Federal lands in the U.S. Pacific Northwest was dramatically reduced under the Northwest Forest Plan in 1994. Despite protection of its remaining forest habitat...
Authors
W. Chris Funk, Eric D. Forsman, Thomas D. Mullins, Susan M. Haig

Use of body mass, footpad length, and wing chord to determine sex in Swainson's Hawks Use of body mass, footpad length, and wing chord to determine sex in Swainson's Hawks

Many studies of avian ecology require an expedient means to determine sex, and the use of molecular techniques has provided an effective and accurate means to determine sex of raptors in the field (Sarasola and Negro 2004, Donohue and Dufty 2006). Sometimes investigators need to rely on morphometric measurements to determine sex of monochromatic species such as Swainson's Hawks (Buteo...
Authors
Michael N. Kochert, James O. McKinley

NCCN Mountain Lakes Monitoring Strategy: Guidelines to Resolution NCCN Mountain Lakes Monitoring Strategy: Guidelines to Resolution

The North Coast and Cascades Network (NCCN) Inventory and Monitoring Program provides funds to its Network Parks to plan and implement the goals and objectives of the National Park Services? (NPS) Inventory and Monitoring (I&M) Program. The primary purpose of the I&M program is to develop and implement a long-term monitoring program in each network. The purpose of this document is to...
Authors
Robert L. Hoffman, Mark H. Huff

Range-wide patterns of greater sage-grouse persistence Range-wide patterns of greater sage-grouse persistence

Aim: Greater sage-grouse (Centrocercus urophasianus), a shrub-steppe obligate species of western North America, currently occupies only half its historical range. Here we examine how broad-scale, long-term trends in landscape condition have affected range contraction. Location: Sagebrush biome of the western USA. Methods: Logistic regression was used to assess persistence and extirpation...
Authors
Cameron L. Aldridge, Scott E. Nielsen, Hawthorne L. Beyer, Mark S. Boyce, John W. Connelly, Steven T. Knick, Michael A. Schroeder

The human footprint in the west: a large-scale analysis of anthropogenic impacts. The human footprint in the west: a large-scale analysis of anthropogenic impacts.

Anthropogenic features such as urbanization, roads, and power lines, are increasing in western United States landscapes in response to rapidly growing human populations. However, their spatial effects have not been evaluated. Our goal was to model the human footprint across the western United States. We first delineated the actual area occupied by anthropogenic features, the physical...
Authors
M. Leu, S.E. Hanser, S.T. Knick

Osprey distribution, abundance, reproductive success and contaminant burdens along lower Columbia River, 1997/1998 versus 2004 Osprey distribution, abundance, reproductive success and contaminant burdens along lower Columbia River, 1997/1998 versus 2004

The osprey (Pandion haliaetus) population nesting along the lower portion of the Columbia River (river mile 29 to 286) increased from 94 in 1997 to 103 occupied nests in 1998 (9.6% annual rate of increase) to 225 occupied nests in 2004 (13.9% annual rate of increase). The more recent rate of population increase was associated with higher reproductive rates than in 1997/1998, and...
Authors
Charles J. Henny, R. A. Grove, J. L. Kaiser

Growth, population structure, and reproduction of western pond turtles (Actinemys marmorata) on the central coast of California Growth, population structure, and reproduction of western pond turtles (Actinemys marmorata) on the central coast of California

We studied the population structure and growth of western pond turtles (Actinemys marmorata) at Vandenberg Air Force Base along the coast of central California in April 1995 and June 1996. We captured 179 individuals (115 males, 27 females) from 7 ponds during 26 days of trapping. Many turtles were adult-sized, but based on scute annuli, 74% were 10 years of age, including many 2- to 3...
Authors
D.J. Germano, G. B. Rathbun

Western juniper and ponderosa pine ecotonal climate-growth relationships across landscape gradients in southern Oregon Western juniper and ponderosa pine ecotonal climate-growth relationships across landscape gradients in southern Oregon

Forecasts of climate change for the Pacific northwestern United States predict warmer temperatures, increased winter precipitation, and drier summers. Prediction of forest growth responses to these climate fluctuations requires identification of climatic variables limiting tree growth, particularly at limits of free species distributions. We addressed this problem at the pine-woodland...
Authors
K.C. Knutson, D.A. Pyke

Demography and movement in a relocated population of Oregon Spotted Frogs (Rana pretiosa): Influence of season and gender Demography and movement in a relocated population of Oregon Spotted Frogs (Rana pretiosa): Influence of season and gender

We used five years of recapture data and Bayesian estimation to assess seasonal survival, movement, and growth of Oregon Spotted Frogs (Rana pretiosa) relocated into created ponds at Dilman Meadow in Oregon, USA. We evaluate hypotheses specific to the relocation and elucidate aspects of R. pretiosa life history that are poorly known. The odds of survival of relocated individuals during...
Authors
N.D. Chelgren, C.A. Pearl, M.J. Adams, J. Bowerman

Analysis of trade-offs between threats of invasion by nonnative brook trout (Salvelinus fontinalis) and intentional isolation for native westslope cutthroat trout (Oncorhynchus clarkii lewisi) Analysis of trade-offs between threats of invasion by nonnative brook trout (Salvelinus fontinalis) and intentional isolation for native westslope cutthroat trout (Oncorhynchus clarkii lewisi)

Native salmonid fishes often face simultaneous threats from habitat fragmentation and invasion by nonnative trout species. Unfortunately, management actions to address one may create or exacerbate the other. A consistent decision process would include a systematic analysis of when and where intentional use or removal of barriers is the most appropriate action. We developed a Bayesian...
Authors
D.P. Peterson, B.E. Rieman, J. B. Dunham, K.D. Fausch, M.K. Young

Space and habitat use by black bears in the Elwha valley prior to dam removal Space and habitat use by black bears in the Elwha valley prior to dam removal

Dam removal and subsequent restoration of salmon to the Elwha River is expected to cause a shift in nutrient dynamics within the watershed. To document how this influx of nutrients and energy may affect black bear (Ursus americanus) ecology, we used radio-telemetry to record movements of 11 male and two female black bears in the Elwha Valley from 2002-06. Our objective was to collect...
Authors
K.A. Sager-Fradkin, K.J. Jenkins, P.J. Happe, J.J. Beecham, R.G. Wright, R.A. Hoffman
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