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Publications

Filter Total Items: 1990

Influence of barriers to movement on within-watershed genetic variation of coastal cutthroat trout

Because human land use activities often result in increased fragmentation of aquatic and terrestrial habitats, a better understanding of the effects of fragmentation on the genetic heterogeneity of animal populations may be useful for effective management. We used eight microsatellites to examine the genetic structure of coastal cutthroat trout (Oncorhynchus clarki clarki) in Camp Creek, an isolat
Authors
John E. B. Wofford, Robert E. Gresswell, Michael A. Banks

Red brome (Bromus rubens subsp. madritensis) in North America: Possible modes for early introductions, subsequent spread

Although invasions by exotic plants have increased dramatically as human travel and commerce have increased, few have been comprehensively described. Understanding the patterns of invasive species’ spread over space and time will help guide management activities and policy. Tracing the earliest appearances of an exotic plant reveals likely sites of introduction, paving the way for genetic studies
Authors
L. F. Salo

Demography and decline of the Mentasta caribou herd, Alaska

We evaluated population trends in the Mentasta caribou (Rangifer tarandus (L., 1758)) herd in Wrangell – St. Elias National Park and Preserve, Alaska, from 1990 to 1997 and determined factors contributing to its decline. We postulated that predation-related mortality of adult females and juveniles was the proximate cause of the decline, and that survival of juvenile caribou reflected interactions
Authors
Kurt J. Jenkins, Neil L. Barten

Sonoran Desert winter annuals affected by density of red brome and soil nitrogen

Red brome [Bromus madritensis subsp. rubens (L.) Husn.] is a Mediterranean winter annual grass that has invaded Southwestern USA deserts. This study evaluated interactions among 13 Sonoran Desert annual species at four densities of red brome from 0 to the equivalent of 1200 plants m−2. We examined these interactions at low (3 μg) and high (537 μg NO3− g soil−1) nitrogen (N) to evaluate the relativ
Authors
L. F. Salo, G. R. McPherson, D. G. Williams

Selection of arboreal termitaria for nesting by cooperatively breeding Micronesian Kingfishers Todiramphus cinnamominus reichenbachii

Limited nest-site availability appears to be an important factor in the evolution of delayed dispersal and cooperative breeding in some cavity-nesting species. The cooperatively breeding Pohnpei subspecies of Micronesian Kingfisher Todiramphus cinnamominus reichenbachii excavates nest cavities from the nests of arboreal termites Nasutitermes spp., or termitaria. In this first published description
Authors
Dylan C. Kesler, Susan M. Haig

Nitrogen retention across a gradient of 15N additions to an unpolluted temperate forest soil in Chile

Accelerated nitrogen (N) inputs can drive nonlinear changes in N cycling, retention, and loss in forest ecosystems. Nitrogen processing in soils is critical to understanding these changes, since soils typically are the largest N sink in forests. To elucidate soil mechanisms that underlie shifts in N cycling across a wide gradient of N supply, we added 15NH415NO3 at nine treatment levels ranging in
Authors
Steven S. Perakis, Jana E. Compton, L. O. Hedin

Terrestrial C sequestration at elevated CO2 and temperature: the role of dissolved organic N loss

We used a simple model of carbon–nitrogen (C–N) interactions in terrestrial ecosystems to examine the responses to elevated CO2 and to elevated CO2 plus warming in ecosystems that had the same total nitrogen loss but that differed in the ratio of dissolved organic nitrogen (DON) to dissolved inorganic nitrogen (DIN) loss. We postulate that DIN losses can be curtailed by higher N demand in response
Authors
Edward B. Rastetter, Steven S. Perakis, Gaius R. Shaver, Goran I. Agren

Diet of introduced bullfrogs (Rana catesbeiana): Predation on and diet overlap with native frogs on Daishan Island, China

We examined diet of introduced Bullfrogs (Rana catesbeiana) and three native frog species (Rana limnocharis, Rana nigromaculata, and Bufo bufo gargarizans) co-occurring at a group of ponds on Daishan Island, east of China, to gain insight into the nature of potential interactions between Bullfrogs and native frog species. For postmetamorphic Bullfrogs, aquatic prey items dominated volumetrically.
Authors
Zhengjun Wu, Y. Li, Y. Wang, Michael J. Adams

Population size and winter distribution of eastern American oystercatchers

Conservation of the eastern subspecies of the American oystercatcher (Haematopus palliatus palliatus) is a high priority in the U.S. Shorebird Conservation Plan, but previous population estimates were unreliable, information on distribution and habitat associations during winter was incomplete, and methods for long-term monitoring had not been developed prior to this survey. We completed the aeria
Authors
Stephen C. Brown, Shiloh A. Schulte, B. Harrington, Brad Winn, Jonathan Bart, Marshall Howe

Effects of management practices on grassland birds: Prairie Falcon

Information on the habitat requirements and effects of habitat management on grassland birds were summarized from information in more than 4,000 published and unpublished papers. A range map is provided to indicate the breeding, year-round, and nonbreeding ranges in the United States and southern Canada. Although birds frequently are observed outside the breeding range indicated, the maps are inte
Authors
John P. DeLong, Karen Steenhof

An annotated bibliography of selected guides for stream habitat improvement in the Pacific Northwest

This annotated bibliography is a response to widespread interest in stream habitat improvement in the Pacific Northwest by land managers, governmental and nongovernmental organizations, and the lay public. Several guides to stream habitat improvement have been written in the past, but may not be easily accessible to people from diverse backgrounds. This annotated bibliography reviews 11 guides to
Authors
R.F. Keim, A.B. Price, T. S. Hardin, Arne E. Skaugset, D.S. Bateman, R. E. Gresswell, S. D. Tesch