Publications
Filter Total Items: 2000
Satellite telemetry and prey sampling reveal contaminant sources to pacific northwest ospreys
Migratory behavior can be an important factor in determining contaminant exposure in avian populations. Accumulation of organochlorine (OC) pesticides while birds are wintering in tropical regions has been cited often as the reason for high concentrations in migrant populations. To explore this issue, we satellite tracked 16 Ospreys (Pandion haliaetus) over the period 1996-2003 from breeding sites
Authors
J. E. Elliott, C.A. Morrissey, C. J. Henny, E.R. Inzunza, P. Shaw
Conservation biology for suites of species: Demographic modeling for Pacific island kingfishers
Conservation practitioners frequently extrapolate data from single-species investigations when managing critically endangered populations. However, few researchers initiate work with the intent of making findings useful to conservation efforts for other species. We presented and explored the concept of conducting conservation-oriented research for suites of geographically separated populations wit
Authors
D.C. Kesler, S. M. Haig
Use of seasonal freshwater wetlands by fishes in a temperate river floodplain
This study examined the use of freshwater wetland restoration and enhancement projects (i.e. non-estuarine wetlands subject to seasonal drying) by fish populations. To quantify fish use of freshwater emergent wetlands and assess the effect of wetland enhancement (i.e. addition of water control structures), two enhanced and two unenhanced emergent wetlands were compared, as well as two oxbow habita
Authors
Julie A. Henning, Robert E. Gresswell, Ian A. Fleming
Occurrence of the amphibian pathogen Batrachochytrium dendrobatidis in Pacific Northwestern USA
Chytridiomycosis (infection by the fungus Batrachochytrium dendrobatidis) has been associated with amphibian declines in at least four continents. We report results of disease screens from 210 pond-breeding amphibians from 37 field sites in Oregon and Washington. We detected B. dendrobatidis on 28% of sampled amphibians, and and we found -> 1 detection of B. dendrobatidis from 43% of sites. Four o
Authors
Christopher A. Pearl, E. L. Bull, D. E. Green, Jay Bowerman, M. J. Adams, A. Hyatt, W. Wente
Nutrient vectors and riparian processing: A review with special reference to African semiarid savanna ecosystems
This review article describes vectors for nitrogen and phosphorus delivery to riparian zones in semiarid African savannas, the processing of nutrients in the riparian zone and the effect of disturbance on these processes. Semiarid savannas exhibit sharp seasonality, complex hillslope hydrology and high spatial heterogeneity, all of which ultimately impact nutrient fluxes between riparian, upland a
Authors
Shayne M. Jacobs, J.S. Bechtold, Harry C. Biggs, N. B. Grimm, S. Lorentz, M.E. McClain, R.J. Naiman, Steven S. Perakis, G. Pinay, M.C. Scholes
Microsatellite variation reveals weak genetic structure and retention of genetic variability in threatened Chinook salmon (Oncorhynchus tshawytscha) within a Snake River watershed
Pacific salmon (Oncorhynchus spp.) have been central to the development of management concepts associated with evolutionarily significant units (ESUs), yet there are still relatively few studies of genetic diversity within threatened and endangered ESUs for salmon or other species. We analyzed genetic variation at 10 microsatellite loci to evaluate spatial population structure and genetic variabil
Authors
Helen Neville, Frank B. Issacs, Russel Thurow, J. B. Dunham, B. Rieman
Biotic soil crusts in relation to topography, cheatgrass, and fire in the Columbia Basin, Washington
We studied lichen and bryophyte soil crust communities in a large public grazing allotment within a sagebrush steppe ecosystem in which the biotic soil crusts are largely intact. The allotment had been rested from grazing for 12 years, but experienced an extensive series of wildfires. In the 350, 4 x 0.5 m plots, stratified by topographic position, we found 60 species or species groups that can be
Authors
Jeanne Ponzetti, B. McCune, David A. Pyke
Dachtal Isomers and Acidic Herbicides and Pesticides in Eggs of Osprey (Pandion haliaetus) from the Seattle and Everett Areas, Washington, U.S.A
Current-use chlorophenoxy herbicides including 2,4-dichlorophenoxyacetic acid, dicamba, triclopyr, dicamba, dimethyl tetrachloroterephthalate (DCPA or dacthal), and the metabolite of pyrethroids, 3-phenoxybenzoic acid (3-PBA), and the fungicide, chlorothalonil, were investigated in the eggs of osprey (Pandion haliaetus) that were collected from 15 sites from five study areas Puget Sound/Seattle ar
Authors
S. Chu, Charles J. Henny, James L. Kaiser, K.G. Drouillard, G.D. Haffner, R.J. Letcher
Arthropod prey of Wilson's Warblers in the understory of Douglas-fir forests
Availability of food resources is an important factor in avian habitat selection. Food resources for terrestrial birds often are closely related to vegetation structure and composition. Identification of plant species important in supporting food resources may facilitate vegetation management to achieve objectives for providing bird habitat. We used fecal analysis to describe the diet of adult Wil
Authors
Joan C. Hagar, Kate Dugger, Edward E. Starkey
The state of the art in raptor electrocution research: A global review
We systematically reviewed the raptor electrocution literature to evaluate study designs and methods used in raptor electrocution research, mitigation, and monitoring, emphasizing original research published in English. Specifically, we wondered if three decades of effort to reduce raptor electrocutions has had positive effects. The majority of literature examined came from North America, western
Authors
Robert N. Lehman, P.L. Kennedy, J. A. Savidge
Thermal, chemical, and optical properties of Crater Lake, Oregon
Crater Lake covers the floor of the Mount Mazama caldera that formed 7700 years ago. The lake has a surface area of 53 km2 and a maximum depth of 594 m. There is no outlet stream and surface inflow is limited to small streams and springs. Owing to its great volume and heat, the lake is not covered by snow and ice in winter unlike other lakes in the Cascade Range. The lake is isothermal in winter e
Authors
Gary L. Larson, Robert L. Hoffman, D. C. McIntire, M. W. Buktenica, Scott Girdner
Fix success and accuracy of GPS radio collars in old-growth temperate coniferous forests
Global Positioning System (GPS) telemetry is used extensively to study animal distribution and resource selection patterns but is susceptible to biases resulting from data omission and spatial inaccuracies. These data errors may cause misinterpretation of wildlife habitat selection or spatial use patterns. We used both stationary test collars and collared free-ranging American black bears (Ursus a
Authors
Kimberly A. Sager-Fradkin, Kurt J. Jenkins, Robert L. Hoffman, P. Happe, J. Beecham, R. G. Wright