Publications
Filter Total Items: 1971
Integrating physical and chemical characteristics of lakes into the glacially influenced landscape of the Northern Cascade Mountains, Washington State, USA
A basic knowledge of the physical and chemical characteristics of lakes is needed by management to make informed decisions to protect water resources. In this study we investigated some of the physical and chemical characteristics of 58 lakes in alpine, subalpine, and forest vegetation zones in a natural area (North Cascades National Park Service Complex) between 1989 and 1993. The objectives of t
Authors
Gary L. Larson, G.A. Lomnicky, Robert Hoffman, W.J. Liss, E. Deimling
Butyltin compounds in river otters (Lutra canadensis) from the northwestern United States
Butyltin compounds, including mono-, di-, and tributyltin (MBT, DBT, and TBT) were measured in livers of 40 adult river otters (Lutra canadensis) collected from rivers and coastal bays in Washington and Oregon, USA. Butyltins were found in all the river otters, at a concentration range of 8.5–2,610 ng/g, WW. The greatest concentration of total butyltins of 2,610 ng/g, WW, was found in a river otte
Authors
K. Kannan, Robert A. Grove, K. Senthilkumar, Charles J. Henny, J. P. Geisy
Detecting long-term hydrological patterns at Crater Lake, Oregon
Tree-ring chronologies for mountain hemlock (Tsuga mertensiana) were used to reconstruct the
water level of Crater Lake, a high-elevation lake in the southern Cascade Range of Oregon.
Reconstructions indicate that lake level since the late 1980s has been lower than at any point in the last 300 years except the early 1930s to mid 1940s. Lake level was consistently higher during the Little Ice Age
Authors
D. L. Peterson, D.G. Silsbee, Kelly T. Redmond
Chlorinated hydrocarbons in livers of American mink (Mustela vison) and river otter (Lutra canadensis) from the Columbia and Fraser River Basins, 1990-1992
We investigated chlorinated hydrocarbon contaminants in aquatic mustelid species on the Fraser and Columbia Rivers of northwestern North America. Carcasses of river otter (Lutra canadensis) (N=24) and mink (Mustela vison) (N=34) were obtained from commercial trappers during the winters of 1990–91 and 1991–92. Pooled liver samples were analyzed for organochlorine pesticides, polychlorinated bipheny
Authors
J. E. Elliott, Charles J. Henny, M.L. Harris, L. K. Wilson, R. J. Norstrom
Fire and aquatic ecosystems in forested biomes of North America
Synthesis of the literature suggests that physical, chemical, and biological elements of a watershed interact with long-term climate to influence fire regime, and that these factors, in concordance with the postfire vegetation mosaic, combine with local-scale weather to govern the trajectory and magnitude of change following a fire event. Perturbation associated with hydrological processes is prob
Authors
Robert E. Gresswell
Variation in age at metamorphosis across a latitudinal gradient for the tailed frog, Ascaphus truei
Tailed frogs (Ascaphus truei) occur in permanent, cold streams in northwestern North America. Their tadpoles reportedly undergo metamorphosis after 2-4 years. Coastal populations that we examined transformed in 2 yr from the Olympic peninsula in Washington to northern Oregon, but in 1 yr from central Oregon to northern California. One inland site in northern California had a 2-yr period. Age at me
Authors
R. Bruce Bury, M. J. Adams
Multiscale habitat associations of the sage sparrow: Implications for conservation biology
No abstract available.
Authors
J.T. Rotenberry, Steven T. Knick
Effects of sample size on KERNEL home range estimates
Kernel methods for estimating home range are being used increasingly in wildlife research, but the effect of sample size on their accuracy is not known. We used computer simulations of 10-200 points/home range and compared accuracy of home range estimates produced by fixed and adaptive kernels with the reference (REF) and least-squares cross-validation (LSCV) methods for determining the amount of
Authors
D.E. Seaman, J.J. Millspaugh, Brian J. Kernohan, Gary C. Brundige, Kenneth J. Raedeke, Robert A. Gitzen
DDE, PCBs, cadmium, lead, and mercury concentrations in rhinoceros auklets from Washington
In July 1981, 5 adult rhinoceros auklets (Cerorhinca monocerata) were captured on the ground near nesting areas on each of Protection and Destruction Islands, Washington. The birds were euthanized, and their livers and kidneys removed and analyzed. Levels (I?g / g wet weight) of DDE (0.11 to 0.95), polychlorinated biphenyls (no residue detected [ND] to 1.1), mercury (0.60 to 1.8), and lead (ND to
Authors
L. J. Blus, R. E. Fitzner, L.L. Leschner, U.W. Wilson
Bat activity in thinned, unthinned, and old-growth forests in western Oregon
Many aspects of the influences of forest management activities on bats (Chiroptera) in the Pacific Northwest are poorly known. We compared thinned and unthinned forest stands of the same age and old-growth forest stands to determine potential differences in structure and amount of use by bats. We hypothesized that activity levels of bats would differ in stands differing in structure as a result of
Authors
Marcia L. Humes, J. P. Hayes, Michael W. Collopy
Creating raptor benefits from powerline problems
Powerlines benefit raptors by providing enhanced nesting and roosting sites. However, they
also can kill raptors by electrocution and raptors can interfere with power transmission. The electrocution problem has been reduced by correcting existing lethal lines and implementing electrocution safe designs for new lines. Remedial actions include pole modifications, perch management and insulation of
Authors
Michael N. Kochert, R.R. Olendorff
Effects of military training activities on shrub-steppe raptors in southwestern Idaho, USA
), northern harriers (Circus cyaneus), burrowing owls (Athene cunicularia), and short-eared owls (Asio flammeus) inside and outside a military training site in the Snake River Birds of Prey National Conservation Area, southwestern Idaho. The Orchard Training Area is used primarily for armored vehicle training and artillery firing by the Idaho Army National Guard. Relative abundance of nesting pair
Authors
Robert N. Lehman, Karen Steenhof, Michael N. Kochert, L.B. Carpenter