Publications
Filter Total Items: 1994
Interannual variation of carbon fluxes from three contrasting evergreen forests: The role of forest dynamics and climate
Interannual variation of carbon fluxes can be attributed to a number of biotic and abiotic controls that operate at different spatial and temporal scales. Type and frequency of disturbance, forest dynamics, and climate regimes are important sources of variability. Assessing the variability of carbon fluxes from these specific sources can enhance the interpretation of past and current observations.
Authors
C.A. Sierra, H.W. Loescher, M. E. Harmon, A.D. Richardson, D.Y. Hollinger, S.S. Perakis
Polybrominated diphenyl ether flame retardants in eggs may reduce reproductive success of ospreys in Oregon and Washington, USA
Spatial and temporal assessments and reports of polybrominated diphenyl ether (PBDE) flame retardants in birds remain sparse. In the present study, PBDEs were detected in all 120 osprey (Pandion haliaetus) eggs collected. The eggs were collected from nests along the Columbia, Willamette and Yakima rivers of Oregon (OR) and Washington (WA) and in Puget Sound (WA) between 2002 and 2007. PBDE congene
Authors
C. J. Henny, J.L. Kaiser, R. A. Grove, B. L. Johnson, R.J. Letcher
Nitrogen dynamics across silvicultural canopy gaps in young forests of western Oregon
Silvicultural canopy gaps are emerging as an alternative management tool to accelerate development of complex forest structure in young, even-aged forests of the Pacific Northwest. The effect of gap creation on available nitrogen (N) is of concern to managers because N is often a limiting nutrient in Pacific Northwest forests. We investigated patterns of N availability in the forest floor and uppe
Authors
A.L. Thiel, S.S. Perakis
Avian response to wildfire in interior Columbia basin shrubsteppe
Wildfire and conversion of sagebrush (Artemisia spp.) shrublands to cheatgrass (Bromus tectorum) grasslands is a serious threat to the shrubsteppe ecosystem, but few studies have documented wildfire's effects on birds with multiple years of pre- and post-fire data. Using data from avian point counts recorded 4 years before and 7 years after a large-scale, severe wildfire in the Columbia Basin of s
Authors
S.L. Earnst, H.L. Newsome, W.L. LaFramboise, N. LaFramboise
Freshwater ecosystems and resilience of Pacific salmon: Habitat Management based on natural variability
In spite of numerous habitat restoration programs in fresh waters with an aggregate annual funding of millions of dollars, many populations of Pacific salmon remain significantly imperiled. Habitat restoration strategies that address limited environmental attributes and partial salmon life-history requirements or approaches that attempt to force aquatic habitat to conform to idealized but ecologic
Authors
P.A. Bisson, J. B. Dunham, G.H. Reeves
Dramatic declines of DDE and other organochlorines in spring migrant Peregrine Falcons from Padre Island, Texas, 1978-2004
Peregrine Falcons (Falco peregrinus) captured in the spring at Padre Island, Texas, nest across the arctic and subarctic from Alaska to Greenland and winter throughout Latin America. Padre Island, located immediately north of the Mexican border, is the peregrines' first landfall in the U.S.A. after spending about 6 mo in Latin America. Blood plasma was collected from spring migrants at Padre Islan
Authors
C. J. Henny, M.A. Yates, W.S. Seegar
Probability of detection of nests and implications for survey design
Surveys based on double sampling include a correction for the probability of detection by assuming complete enumeration of birds in an intensively surveyed subsample of plots. To evaluate this assumption, we calculated the probability of detecting active shorebird nests by using information from observers who searched the same plots independently. Our results demonstrate that this probability vari
Authors
P.A. Smith, J. Bart, Richard B. Lanctot, B. J. McCaffery, S. Brown
A spatial model to prioritize sagebrush landscapes in the intermountain west (U.S.A.) for restoration
The ecological integrity of Sagebrush (Artemisia spp.) ecosystems in the Intermountain West (U.S.A.) has been diminished by synergistic relationships among human activities, spread of invasive plants, and altered disturbance regimes. An aggressive effort to restore Sagebrush habitats is necessary if we are to stabilize or improve current habitat trajectories and reverse declining population trends
Authors
C.W. Meinke, S.T. Knick, D.A. Pyke
Effects of horseshoe crab harvest in delaware bay on red knots: Are harvest restrictions working?
Each May, red knots (Calidris canutus rufa) congregate in Delaware Bay during their northward migration to feed on horseshoe crab eggs (Limulus polyphemus) and refuel for breeding in the Arctic. During the 1990s, the Delaware Bay harvest of horseshoe crabs for bait increased 10-fold, leading to a more than 90% decline in the availability of their eggs for knots. The proportion of knots achieving w
Authors
L. J. Niles, J. Bart, H.P. Sitters, A.D. Dey, K.E. Clark, P.W. Atkinson, Allan J. Baker, K.A. Bennett, K.S. Kalasz, N.A. Clark, J. Clark, S. Gillings, A.S. Gates, P.M. Gonzalez, D.E. Hernandez, C.D.T. Minton, R. I. G. Morrison, R.R. Porter, R.K. Ross, C.R. Veitch
Zooplankton assemblages in montane lakes and ponds of Mount Rainier National Park, Washington State, USA
Water quality and zooplankton samples were collected during the ice-free periods between 1988 and 2005 from 103 oligotrophic montane lakes and ponds located in low forest to alpine vegetation zones in Mount Rainier National Park, Washington State, USA. Collectively, 45 rotifer and 44 crustacean taxa were identified. Most of the numerically dominant taxa appeared to have wide niche breadths. The av
Authors
G.L. Larson, R. Hoffman, C. D. McIntire, G. Lienkaemper, B. Samora
A sightability model for mountain goats
Unbiased estimates of mountain goat (Oreamnos americanus) populations are key to meeting diverse harvest management and conservation objectives. We developed logistic regression models of factors influencing sightability of mountain goat groups during helicopter surveys throughout the Cascades and Olympic Ranges in western Washington during summers, 20042007. We conducted 205 trials of the ability
Authors
C.G. Rice, K.J. Jenkins, W.-Y. Chang
Unusual raptor nests around the world
From surveys in many countries, we report raptors using unusual nesting materials (e.g., paper money, rags, metal, antlers, and large bones) and unusual nesting situations. For example, we documented nests of Steppe Eagles Aquila nipalensis and Upland Buzzards Buteo hemilasius on the ground beside well-traveled roads, Saker Falcon Falco cherrug eyries in attics and a cistern, and Osprey Pandion ha
Authors
D. H. Ellis, T. Craig, E. Craig, S. Postupalsky, C.T. LaRue, R.W. Nelson, D. W. Anderson, C. J. Henny, J. Watson, B.A. Millsap, J.W. Dawson, K.L. Cole, E.M. Martin, A. Margalida, P. Kung