Publications
Filter Total Items: 1994
Population estimates of Nearctic shorebirds
Estimates are presented for the population sizes of 53 species of Nearctic shorebirds occurring regularly in North America, plus four species that breed occasionally. Shorebird population sizes were derived from data obtained by a variety of methods from breeding, migration and wintering areas, and formal assessments of accuracy of counts or estimates are rarely available. Accurate estimates exist
Authors
R. I. G. Morrison, Robert E. Gill, B. A. Harrington, S. K. Skagen, G. W. Page, C. L. Gratto-Trevor, S. M. Haig
Pond permanence and the effects of exotic vertebrates on anurans
In many permanent ponds throughout western North America, the introduction of a variety of exotic fish and bullfrogs (Rana catesbeiana) correlates with declines in native amphibians. Direct effects of exotics are suspected to be responsible for the rarity of some native amphibians and are one hypothesis to explain the prevalence of amphibian declines in western North America. However, the predicti
Authors
M. J. Adams
Species richness and abundance of ectomycorrhizal basidiomycete sporocarps on a moisture gradient in the Tsuga heterophylla zone
Sporocarps of epigeous ectomycorrhizal fungi and vegetation data were collected from eight Tsuga heterophylla (Raf.) Sarg. - Pseudotsuga menziesii (Mirb.) Franco stands along a wet to dry gradient in Olympic National Park, Washington, U.S.A. One hundred and fifty species of ectomycorrhizal fungi were collected from a total sample area of 2.08 ha. Over 2 years, fungal species richness ranged from 1
Authors
Thomas E. O'Dell, Joseph F. Ammirati, Edward G. Schreiner
Demographic characteristics and population modeling: Chapter 8 in Status, ecology and conservation of the Southwestern Willow Flycatcher (RMRS-GTR-60)
An understanding of the basic demography of a species is necessary to estimate and evaluate population trends. The relative impact of different demographic parameters on growth rates can be assessed through a sensitivity analysis, in which different parameters are altered singly to assess the effect on population growth. Identification of critical parameters can allow managers to focus their effor
Authors
Scott H. Stoleson, Mary J. Whitfield, Mark K. Sogge
[Book Review] Sunrise to Paradise: The story of Mount Rainier National Park
No abstract available.
Authors
D. L. Peterson
A survey of current breeding habitats: Chapter 5 in Status, ecology and conservation of the Southwestern Willow Flycatcher (RMRS-GTR-60)
The distribution and abundance of a species across a landscape depends, in part, on the distribution and abundance of appropriate habitat. If basic resource needs such as food, water, and cover are not present, then that species is excluded from the area. Scarcity of appropriate habitat is generally the key reason for the status of most rare and endangered species. An understanding of an endangere
Authors
Mark K. Sogge, Robert M. Marshall
Breeding season ecology: Chapter 6 in Status, ecology and conservation of the Southwestern Willow Flycatcher (RMRS-GTR-60)
The willow flycatcher (Empidonax traillii) breeds across much of the conterminous United States and in portions of extreme southern Canada. As might be expected in such a wide-ranging species, willow fly- catchers in different portions of the range exhibit differences in appearance, song, and ecological characteristics. The intent of this chapter is to provide information on the breeding-season ec
Authors
Mark K. Sogge
[Book Review] Yellowstone and the biology of time- Photographs across a century
No abstract available.
Authors
D. L. Peterson
Assumptions and practical considerations in the design and interpretation of echolocation-monitoring studies
No abstract available.
Authors
J. P. Hayes
Growth and population structure of Emydoidea blandingii from western Nebraska
No abstract available.
Authors
D.J. Germano, R. Bruce Bury, M. Jennings
Reports on Alaska in non-USGS publications released in 1998 that include USGS authors: A section in Geologic studies in Alaska by the U.S. Geological Survey, 1998
No abstract available.
Authors
John P. Galloway, Susan Toussaint
First-year movements by juvenile Mexican spotted owls in the Canyonlands of Utah
We studied first-year movements of Mexican Spotted Owls (Strix occidentalis lucida) during natal dispersal in canyonlands of southern Utah. Thirty-one juvenile Mexican Spotted Owls were captured and radiotracked during 1992-95 to examine behavior and conduct experiments related to the onset of natal dispersal. Juvenile Spotted Owls dispersed from their nest areas during September to October each y
Authors
D.W. Willey, Charles van Riper