Publications
Below is a list of available NOROCK peer reviewed and published science. If you are in search of a specific publication and cannot find it below or through a search, please contact twojtowicz@usgs.gov.
Filter Total Items: 1197
Habitat-based adaptive management at Mount Haggin Wildlife Management Area
The 22,743-hectare Mount Haggin Wildlife Management Area was purchased in 1976, in part for moose (Alces alces) winter range. Observed moose populations climbed from a low of 7 in 1976 to a high of 56 in 2000. A 4-step management program was initiated in 2000 consisting of definition of management objective, monitoring to determine if the objective was attained, developing a management strategy, a
Authors
R.B. Keigley, C.W. Fager
Spatial heterogeneity influences native and nonnative plant species richness
No abstract available.
Authors
S. Kumar, T.J. Stohlgren, G.W. Chong
Distribution of boreal toad populations in relation to estimated UV-B dose in Glacier National Park, Montana, USA
A recent increase in ultraviolet B radiation is one hypothesis advanced to explain suspected or documented declines of the boreal toad (Bufo boreas Baird and Girard, 1852) across much of the western USA, where some experiments have shown ambient UV-B can reduce embryo survival. We examined B. boreas occupancy relative to daily UV-B dose at 172 potential breeding sites in Glacier National Park, Mon
Authors
B. R. Hossack, S. A. Diamond, P. S. Corn
Divergent patterns of abundance and age-class structure of headwater stream tadpoles in burned and unburned watersheds
Wildfire is a potential threat to many species with narrow environmental tolerances like the Rocky Mountain tailed frog (Ascaphus montanus Mittleman and Myers, 1949), which inhabits a region where the frequency and intensity of wildfires are expected to increase. We compared pre- and post-fire counts of tadpoles in eight streams in northwestern Montana to determine the effects of wildfire on A. mo
Authors
B. R. Hossack, P. S. Corn, D.B. Fagre
Evaluating plant invasions from both habitat and species perspectives
We present an approach to quantitatively assess nonnative plant invasions at landscape scales from both habitat and species perspectives. Our case study included 34 nonnative species found in 142 plots (0.1 ha) in 14 vegetation types within the Grand Staircase-Escalante National Monument, Utah. A plot invasion index, based on nonnative species richness and cover, showed that only 16 of 142 plots w
Authors
G.W. Chong, Yuka Otsuki, T.J. Stohlgren, D. Guenther, P. Evangelista, C. Villa, A. Waters
Effects of feral horses in Great Basin landscapes on soils and ants: Direct and indirect mechanisms
We compared soil-surface penetration resistance and abundance of ant mounds at 12 western Great Basin sites (composed of 19 plots) either grazed by feral horses (Equus caballus) or having had horses removed for the last 10–14 years. Across this broad spatial domain (3.03 million ha), we minimized confounding due to abiotic factors by selecting horse-occupied and horse-removed sites with similar as
Authors
E.A. Beever, J. E. Herrick
Survival and growth of age-0 steelhead after surgical implantation of 23-mm passive integrated transponders
Little information is available on the effects of implanting 23-mm passive integrated transponder (PIT) tags in salmonids less than 90 mm fork length (FL). Using juvenile steelhead Oncorhynchus mykiss (range, 73–97 mm FL), we compared instantaneous growth rates and survival among three experimental groups: control, surgery with no tag, and surgery with tag. Survival rate was lower for tagged fish
Authors
D.S. Bateman, R. E. Gresswell
Juvenile salmonid use of freshwater emergent wetlands in the floodplain and its implications for conservation management
A recent trend of enhancing freshwater emergent wetlands for waterfowl and other wildlife has raised concern about the effects of such measures on juvenile salmonids. We undertook this study to quantify the degree and extent of juvenile Pacific salmon Oncorhynchus spp. utilization of enhanced and unenhanced emergent wetlands within the floodplain of the lower Chehalis River, Washington, and to det
Authors
Julie A. Henning, Robert E. Gresswell, Ian A. Fleming
A spatially explicit approach for evaluating relationships among coastal cutthroat trout, habitat, and disturbance in small Oregon streams
Abstract has not been submitted
Authors
R. E. Gresswell, C.E. Torgersen, D.S. Bateman, T.J. Guy, S.R. Hendricks, J. E. B. Wofford
Forest reproduction along a climatic gradient in the Sierra Nevada, California
To elucidate broad-scale environmental controls of coniferous forest reproduction in the Sierra Nevada, California, we monitored reproduction for 5 years in 47 plots arrayed across a steep elevational (climatic) gradient. We found that both absolute seedling densities (stems < 1.37 m) and seedling densities relative to overstory parent tree basal area declined sharply with elevation. Rates of seed
Authors
Phillip J. van Mantgem, Nathan L. Stephenson, Jon E. Keeley
Remote sensing sensitivity to fire severity and fire recovery
The paper examines fundamental ways that geospatial data on fire severity and recovery are influenced by conditions of the remote sensing. Remote sensing sensitivities are spatial, temporal and radiometric in origin. Those discussed include spatial resolution, the sampling time of year, and time since fire. For standard reference, sensitivities are demonstrated with examples drawn from an archive
Authors
C.H. Key
Climatic variability, ecosystem dynamics, and disturbance in mountain protected areas
No abstract available
Authors
Daniel B. Fagre