Skip to main content
U.S. flag

An official website of the United States government

Publications

Filter Total Items: 1990

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

Widespread occurrence of the chytrid fungus batrachochytrium dendrobatidis on oregon spotted frogs (rana pretiosa)

The pathogen Batrachochytrium dendrobatidis (Bd) has been associated with amphibian declines in multiple continents, including western North America. We investigated Bd prevalence in Oregon spotted frog (Rana pretiosa), a species that has declined across its range in the Pacific Northwest. Polymerase chain reaction analysis of skin swabs indicated that Bd was prevalent within populations (420 of 6
Authors
C.A. Pearl, J. Bowerman, M.J. Adams, N.D. Chelgren

Factors influencing coastal cutthroat trout (Oncorhynchus clarkii clarkii) seasonal survival rates: A spatially continuous approach within stream networks

Mark-recapture methods were used to examine watershed-scale survival of coastal cutthroat trout (Oncorhynchus clarkii clarkii) from two headwater stream networks. A total of 1725 individuals (???100 mm, fork length) were individually marked and monitored seasonally over a 3-year period. Differences in survival were compared among spatial (stream segment, subwatershed, and watershed) and temporal (
Authors
A.M. Berger, R. E. Gresswell

Site fidelity, mate fidelity, and breeding dispersal in American kestrels

We assessed mate fidelity, nest-box fidelity, and breeding dispersal distances of American Kestrels (falco sparverius) nesting in boxes in southwestern Idaho from 1990 through 2006. Seventy-seven percent of boxes had different males and 87% had different females where nest-box occupants were identified in consecutive years. High turnover rates were partly a result of box-switching. Forty-eight per
Authors
K. Steenhof, B.E. Peterson

Behavior and reproductive success of rock sandpipers breeding on the Yukon-Kuskokwim river delta, Alaska

We studied Rock Sandpiper (Calidris ptilocnemis) breeding behavior and monitored reproductive success from 1998 to 2005 on the Yukon-Kuskokwim River Delta, Alaska, USA. We banded 24 adults and monitored 45 nests. Annual return rate of adults ranged between 67 and 100%. Six pairs of Rock Sandpipers bred at our study site for ???2 years, and among these we did not observe mate change (i.e., when bot
Authors
M. Johnson, J.R. Conklin, B. L. Johnson, B. J. McCaffery, S. M. Haig, J. R. Walters