Publications
Filter Total Items: 1994
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 incorporate
Authors
David John Mattson, Kim Barber, Ralene Maw, Roy Renkin
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
Influence of forest management on headwater stream amphibians at multiple spatial scales
Background
Amphibians are important components of headwater streams in forest ecosystems of the Pacific Northwest (PNW). They comprise the highest vertebrate biomass and density in these systems and are integral to trophic dynamics both as prey and as predators. The most commonly encountered amphibians in PNW headwater streams include the Pacific giant salamander (Dicamptodon tenebrosus), the t
Authors
Margo Stoddard, John P. Hayes, Janet L. Erickson
Seed and vegetative production of shrubs and growth of understory conifer regeneration
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) were sampl
Authors
B. Wender, C. Harrington, J. C. Tappeiner
Effects of constant and cyclical thermal regimes on growth and feeding of juvenile cutthroat trout of variable sizes
The effects of constant (12, 18, and 24 °C) and cyclical (daily variation of 15–21 and 12–24 °C) thermal regimes on the growth and feeding of Lahontan cutthroat trout (Oncorhynchus clarki henshawi) of variable sizes were examined. Higher constant temperatures (i.e., 24 °C) and more variable daily temperatures (i.e., 12–24 °C daily cycle) negatively affected growth rates. As fish mass increased (fr
Authors
M.H. Meeuwig, J. B. Dunham, J. P. Hayes, G.L. Vinyard
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 standarda??a
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
Interannual variability in aboveground tree growth in Stehekin River watershed, North Cascade Range, Washington
Many forests in the Pacific Northwest region of North America are both highly productive and sensitive to climate. The combination of productivity and sensitivity makes forests vulnerable to changes in future climate and most likely to feed back to the regional carbon cycle. We reconstructed basal area increment (BAI) for 20 yr using tree-ring increments and diameter to identify species-specific r
Authors
Amy E. Hessl, D. L. Peterson
A video surveillence system for monitoring raptor nests in a temperate rainforest environment
No abstract available.
Authors
S.B. Lewis, P. DeSimone, K. Titus, Mark R. Fuller
A comparison of three methods for assessing raptor diet during the breeding season
Video recording of prey deliveries to nests is a new technique for collecting data on raptor diet, but no thorough comparison of results from traditional methods based on collections of prey remains and pellets has been undertaken. We compared data from these 3 methods to determine relative merits of different methods for assessing raptor diet as part of a study of the breeding-season diet of nort
Authors
S.B. Lewis, Mark R. Fuller, K. Titus
Subspecific relationships and genetic structure in the spotted owl
Hierarchical genetic structure was examined in the three geographically-defined subspecies of spotted owl (Strix occidentalis) to define relationships among subspecies and quantify variation within and among regional and local populations. Sequences (522 bp) from domains I and II of the mitochondrial control region were analyzed for 213 individuals from 30 local breeding areas. Results confirmed s
Authors
Susan M. Haig, E.D. Forsman, Thomas D. Mullins
Responses of Ambystoma gracile to the removal of introduced nonnative fish from a mountain lake
Introduced, nonnative brook trout (Salvelinus fontinalis) were removed from a mountain lake in Mount Rainier National Park, Washington, to examine the capacity of native Ambystoma gracile (Northwestern Salamander) in the lake to respond to the intentional removal of fish. Temporal trends (Δ̄N) were calculated for A. gracile larvae/neotene and egg mass relative abundances in the Fish Removal and an
Authors
Robert L. Hoffman, Gary L. Larson, B. Samora
Salamanders and introduced fish in mountain lakes of two Pacific Northwest parks
No abstract available.
Authors
Gary L. Larson, Robert L. Hoffman