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Publications

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Flower and fruit production of understory shrubs in western Washington and Oregon Flower and fruit production of understory shrubs in western Washington and Oregon

We observed flower and fruit production for nine understory shrub species in western Washington and Oregon and examined the relationships between shrub reproductive output and plant size, plant age, site factors, and overstory density to determine the factors that control flowering or fruiting in understory shrubs. In Washington, 50 or more shrubs or microplots (for rhizomatous species)...
Authors
B. Wender, C. Harrington, J. C. Tappeiner

Pattern detection in stream networks: Quantifying spatial variability in fish distribution Pattern detection in stream networks: Quantifying spatial variability in fish distribution

Biological and physical properties of rivers and streams are inherently difficult to sample and visualize at the resolution and extent necessary to detect fine-scale distributional patterns over large areas. Satellite imagery and broad-scale fish survey methods are effective for quantifying spatial variability in biological and physical variables over a range of scales in marine...
Authors
Christian E. Torgersen, Robert E. Gresswell, Douglas S. Bateman

Coefficients of productivity for Yellowstone's grizzly bear habitat Coefficients of productivity for Yellowstone's grizzly bear habitat

This report describes methods for calculating coefficients used to depict habitat productivity for grizzly bears in the Yellowstone ecosystem. Calculations based on these coefficients are used in the Yellowstone Grizzly Bear Cumulative Effects Model to map the distribution of habitat productivity and account for the impacts of human facilities. The coefficients of habitat productivity...
Authors
David John Mattson, Kim Barber, Ralene Maw, Roy Renkin

Modeling demographic performance of northern spotted owls relative to forest habitat in Oregon Modeling demographic performance of northern spotted owls relative to forest habitat in Oregon

Northern spotted owls (Strix occidentalis caurina) are known to be associated with late-successional forests in the Pacific Northwest of the United States, but the effects of habitat on their demographic performance are relatively unknown. We developed statistical models relating owl survival and productivity to forest cover types within the Roseburg Study Area in the Oregon Coast Range...
Authors
Gail S. Olson, Elizabeth M. Glenn, Robert G. Anthony, Eric D. Forsman, Janice A. Reid, Peter J. Loschl, William J. Ripple

The importance of wood in headwater streams of the Oregon Coast Range The importance of wood in headwater streams of the Oregon Coast Range

Although headwater streams comprise the majority of stream length in mountainous regions, little is known about their form and function in comparison to higher-order rivers. A better understanding of the role of headwater streams in routing water, wood, and sediment is needed to clarify the physical and biological connections among uplands, riparian zones, and downstream reaches.
Authors
Christine May, Robert E. Gresswell, Janet L. Erickson

Effects of the wildfire on growth of cutthroat trout in Yellowstone Lake Effects of the wildfire on growth of cutthroat trout in Yellowstone Lake

This chapter discusses the effects of wildfire on the growth of cutthroat trout in Yellowstone Lake. Trends in year-to-year variation in growth for individual age groups and 25 mm length groups of cutthroat trout in Yellowstone Lake were examined in an attempt to detect shifts in growth patterns associated with the fires. Approximately 100,000 ha of the Yellowstone Lake watershed burned...
Authors
R. E. Gresswell

Density estimation in wildlife surveys Density estimation in wildlife surveys

Several authors have recently discussed the problems with using index methods to estimate trends in population size. Some have expressed the view that index methods should virtually never be used. Others have responded by defending index methods and questioning whether better alternatives exist. We suggest that index methods are often a cost-effective component of valid wildlife...
Authors
Jonathan Bart, Sam Droege, Paul E. Geissler, Bruce G. Peterjohn, C. John Ralph

Roosevelt elk density and social segregation: Foraging behavior and females avoiding larger groups of males Roosevelt elk density and social segregation: Foraging behavior and females avoiding larger groups of males

Intersexual social segregation at small spatial scales is prevalent in ruminants that are sexually dimorphic in body size. Explaining social segregation, however, from hypotheses of how intersexual size differences affects the foraging process of males and females has had mixed results. We studied whether body size influences on forage behavior, intersexual social incompatibility or both...
Authors
F. Weckerly, K. McFarland, M. Ricca, K. Meyer

Thermal characteristics of wild and captive Micronesian Kingfisher nesting habitats Thermal characteristics of wild and captive Micronesian Kingfisher nesting habitats

To provide information for managing the captive population of endangered Guam Micronesian kingfishers (Halcyon cinnamomina cinnamomina), four biologically relevant thermal metrics were compared among captive facilities on the United States mainland and habitats used by wild Micronesian kingfishers on the island of Pohnpei (H. c. reichenbachii), Federated States of Micronesia...
Authors
Dylan C. Kesler, Susan M. Haig

The case for regime-based water quality standards The case for regime-based water quality standards

Conventional water quality standards have been successful in reducing the concentration of toxic substances in US waters. However, conventional standards are based on simple thresholds and are therefore poorly structured to address human-caused imbalances in dynamic, natural water quality parameters, such as nutrients, sediment, and temperature. A more applicable type of water quality...
Authors
Geoffrey C. Poole, J. B. Dunham, D.M. Keenan, S.T. Sauter, D.A. McCullough, Christopher Mebane, Jeffrey C. Lockwood, Don A. Essig, Mark P. Hicks, Debra J. Sturdevant, E.J. Materna, M. Spalding, John Risley, Marianne Deppman

Genetic identification of spotted owls, barred owls, and their hybrids: Legal implications of hybrid identity Genetic identification of spotted owls, barred owls, and their hybrids: Legal implications of hybrid identity

Recent population expansion of Barred Owls ( Strix varia) into western North America has led to concern that they may compete with and further harm the Northern Spotted Owl ( S. occidentalis caurina), which is already listed as threatened under the U.S. Endangered Species Act (ESA). Because they hybridize, there is a legal need under the ESA for forensic identification of both species...
Authors
Susan M. Haig, Liv Wennerberg, Thomas D. Mullins, E.D. Forsman, P. Trail
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