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Publications

Filter Total Items: 1990

Survey trends of North American shorebirds: Population declines or shifting distributions?

We analyzed data from two surveys of fall migrating shorebirds in central and eastern North America to estimate annual trends in means per survey and to determine whether trends indicate a change in population size or might have been caused by other factors. The analysis showed a broad decline in means per survey in Atlantic Canada and the northeastern United States (North Atlantic region). For ex
Authors
Jonathan Bart, Stephen Brown, Brian A. Harrington, R.I. Guy Morrison

State factor relationships of dissolved organic carbon and nitrogen losses from unpolluted temperate forest watersheds

We sampled 100 unpolluted, old-growth forested watersheds, divided among 13 separate study areas over 5 years in temperate southern Chile and Argentina, to evaluate relationships among dominant soil-forming state factors and dissolved carbon and nitrogen concentrations in watershed streams. These watersheds provide a unique opportunity to examine broad-scale controls over carbon (C) and nitrogen (
Authors
S.S. Perakis, L. O. Hedin

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