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: 1300
The ecological future of the North American bison: Conceiving long-term, large-scale conservation of a species The ecological future of the North American bison: Conceiving long-term, large-scale conservation of a species
Many wide-ranging mammal species have experienced significant declines over the last 200 years; restoring these species will require long-term, large-scale recovery efforts. We highlight 5 attributes of a recent range-wide vision-setting exercise for ecological recovery of the North American bison (Bison bison) that are broadly applicable to other species and restoration targets. The...
Authors
E.W. Sanderson, Kent Redford, Bill Weber, K. Aune, Dick Baldes, J. Berger, Dave Carter, C. Curtin, James N. Derr, S.J. Dobrott, Eva Fearn, Craig Fleener, Steven C. Forrest, Craig Gerlach, C. Cormack Gates, J.E. Gross, P. Gogan, Shaun M. Grassel, Jodi A. Hilty, Marv Jensen, Kyran E. Kunkel, Duane Lammers, R. List, Karen Minkowski, Tom Olson, Chris Pague, Paul B. Robertson, Bob Stephenson
Using bioenergetics modeling to estimate consumption of native juvenile salmonids by nonnative northern pike in the Upper Flathead River System, Montana Using bioenergetics modeling to estimate consumption of native juvenile salmonids by nonnative northern pike in the Upper Flathead River System, Montana
Introductions of nonnative northern pike Esox lucius have created recreational fisheries in many waters in the United States and Canada, yet many studies have shown that introduced northern pike may alter the composition and structure of fish communities through predation. We estimated the abundance of nonnative northern pike (2002-2003) and applied food habits data (1999-2003) to...
Authors
C.C. Muhlfeld, D.H. Bennett, Steinhorst R. Kirk, B. Marotz, M. Boyer
Riparian plant community structure in a managed hydrological regime Riparian plant community structure in a managed hydrological regime
The hydrology of the Snake River in Grand Teton National Park is partly determined by releases from Jackson Lake Dam. The dam was first built in 1908 and became part of the National Park system when GTNP was expanded to include most of Jackson Hole. Completion of the present structure of Jackson Lake Dam occurred in 1917 and resulted in an increase above the natural level of Jackson Lake...
Authors
Sabine Mellman-Brown, Dave Roberts, Bruce H. Pugesek
Evaluation of rules to distinguish unique female grizzly bears with cubs in Yellowstone Evaluation of rules to distinguish unique female grizzly bears with cubs in Yellowstone
The United States Fish and Wildlife Service uses counts of unduplicated female grizzly bears (Ursus arctos) with cubs-of-the-year to establish limits of sustainable mortality in the Greater Yellowstone Ecosystem, USA. Sightings are dustered into observations of unique bears based on an empirically derived rule set. The method has never been tested or verified. To evaluate the rule set...
Authors
C.C. Schwartz, M.A. Haroldson, S. Cherry, K.A. Keating
Browse evaluation of tall shrubs based on direct measurement of a management objective Browse evaluation of tall shrubs based on direct measurement of a management objective
The monitoring of Geyer willow was based on the following management objective: Browsing will prevent fewer than 50 percent of Geyer willow shrubs from growing taller than 3 m . Three questions were addressed: (1) Is browsing a potential factor? (2) If so, can young plants grow taller than 3 meters? (3) If not, is browsing the dominant factor? All shrubs were intensely browsed. With a...
Authors
R.B. Keigley, M.R. Frisina
Observations of mixed-aged litters in brown bears Observations of mixed-aged litters in brown bears
We report on 3 cases of mixed-aged litters (young born in different years) in brown bears (Ursus arctos); in 1 instance the cub-of-the-year (hereafter called cubs) died in the den. Two cases occurred in Sweden after mothers were separated from their young during the breeding season. In one, the mother was separated from the accompanying cub for at least 12.5 hours and possibly up to 3.3...
Authors
J. E. Swenson, M.A. Haroldson
A low intensity sampling method for assessing blue crab abundance at Aransas National Wildlife Refuge and preliminary results on the relationship of blue crab abundance to whooping crane winter mortality A low intensity sampling method for assessing blue crab abundance at Aransas National Wildlife Refuge and preliminary results on the relationship of blue crab abundance to whooping crane winter mortality
We sampled blue crabs (Callinectes sapidus) in marshes on the Aransas National Wildlife Refuge, Texas from 1997 to 2005 to determine whether whooping crane (Grus americana) mortality was related to the availability of this food source. For four years, 1997 - 2001, we sampled monthly from the fall through the spring. From these data, we developed a reduced sampling effort method that...
Authors
Bruce H. Pugesek, Michael J. Baldwin, Thomas Stehn
Challenges of DNA-based mark-recapture studies of American black bears Challenges of DNA-based mark-recapture studies of American black bears
We explored whether genetic sampling would be feasible to provide a region-wide population estimate for American black bears (Ursus americanus) in the southern Appalachians, USA. Specifically, we determined whether adequate capture probabilities (p >0.20) and population estimates with a low coefficient of variation (CV
Authors
K.E. Settlage, F.T. Van Manen, J. D. Clark, T.L. King
Wildlife health initiatives in Yellowstone National Park Wildlife health initiatives in Yellowstone National Park
No abstract available.
Authors
Paul C. Cross, G. Plumb
Spatial design and strength of spatial signal: Effects on covariance estimation Spatial design and strength of spatial signal: Effects on covariance estimation
In a spatial regression context, scientists are often interested in a physical interpretation of components of the parametric covariance function. For example, spatial covariance parameter estimates in ecological settings have been interpreted to describe spatial heterogeneity or “patchiness” in a landscape that cannot be explained by measured covariates. In this article, we investigate...
Authors
Kathryn M. Irvine, Alix I. Gitelman, Jennifer A. Hoeting
Results of chemical analyses of soil, shale, and soil/shale extract from the Mancos Shale formation in the Gunnison Gorge National Conservation Area, southwestern Colorado, and at Hanksville, Utah Results of chemical analyses of soil, shale, and soil/shale extract from the Mancos Shale formation in the Gunnison Gorge National Conservation Area, southwestern Colorado, and at Hanksville, Utah
Results of chemical and some isotopic analyses of soil, shale, and water extracts collected from the surface, trenches, and pits in the Mancos Shale are presented in this report. Most data are for sites on the Gunnison Gorge National Conservation Area (GGNCA) in southwestern Colorado. For comparison, data from a few sites from the Mancos landscape near Hanksville, Utah, are included...
Authors
Michele L.W. Tuttle, Juli Fahy, Richard I. Grauch, Bridget A. Ball, Geneva W. Chong, John G. Elliott, John J. Kosovich, Keith E. Livo, Lisa L. Stillings
Evaluating shading bias in malaise and intercept traps Evaluating shading bias in malaise and intercept traps
Foresters are increasingly focusing on landscape level management regimes. At the landscape level, managed acreage may differ substantially in structure and micro-climatic conditions. Trapping is a commonly used method to evaluate changes in insect communities across landscapes. Among those trapping techniques, Malaise and window-pane traps are conveniently deployed to collect large...
Authors
Kathryn M. Irvine, Stephen A. Woods