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Fine-scale natal homing and localized movement as shaped by sex and spawning habitat in chinook salmon Fine-scale natal homing and localized movement as shaped by sex and spawning habitat in chinook salmon

Natal homing is a hallmark of the life history of salmonid fishes, but the spatial scale of homing within local, naturally reproducing salmon populations is still poorly understood. Accurate homing (paired with restricted movement) should lead to the existence of fine-scale genetic structuring due to the spatial clustering of related individuals on spawning grounds. Thus, we explored the...
Authors
Helen Neville, Daniel Isaak, J. B. Dunham, Russel Thurow, B. Rieman

Influence of alternative silviculture on small mammals Influence of alternative silviculture on small mammals

HIGHLIGHT: A variety of harvest methods promote diversity within forests while still generating income. For example, recent studies have shown that when dead wood is left on the forest floor during harvest, biodiversity increases. A new Cooperative Forest Ecosystem Research (CFER) program fact sheet summarizes how small mammals respond to dead wood in forests that are harvested with...
Authors
David L. Waldien, John P. Hayes

Populations and habitat relationships of Piute ground squirrels in southwest Idaho Populations and habitat relationships of Piute ground squirrels in southwest Idaho

Piute ground squirrels (Spermophilus mollis idahoensis) are normally above ground from late January until late June or early July in the Snake River Birds of Prey National Conservation Area in southwestern Idaho. In 2002 they were rarely seen above ground after early May. Because of the ecological importance of ground squirrels for nesting raptors and other species, we sought to...
Authors
Karen Steenhof, Eric Yensen, Michael N. Kochert, K. Gage

GIS-based niche modeling for mapping species' habitats GIS-based niche modeling for mapping species' habitats

Ecological a??niche modelinga?? using presence-only locality data and large-scale environmental variables provides a powerful tool for identifying and mapping suitable habitat for species over large spatial extents. We describe a niche modeling approach that identifies a minimum (rather than an optimum) set of basic habitat requirements for a species, based on the assumption that...
Authors
J.T. Rotenberry, K.L. Preston, S. Knick

Taxonomic considerations in listing subspecies under the U.S. Endangered Species Act Taxonomic considerations in listing subspecies under the U.S. Endangered Species Act

The U.S. Endangered Species Act (ESA) allows listing of subspecies and other groupings below the rank of species. This provides the U.S. Fish and Wildlife Service and the National Marine Fisheries Service with a means to target the most critical unit in need of conservation. Although roughly one-quarter of listed taxa are subspecies, these management agencies are hindered by...
Authors
S. M. Haig, E.A. Beever, Steven M. Chambers, Hope M. Draheim, Bruce D. Dugger, Susie Dunham, Elise Elliott-Smith, Joseph B. Fontaine, Dylan C. Kesler, Brian J. Knaus, Iara F. Lopes, Peter J. Loschl, Thomas D. Mullins, Lisa M. Sheffield

Taricha granulosa (Rough-skinned newt). Summer habitat and aggregation. Taricha granulosa (Rough-skinned newt). Summer habitat and aggregation.

Terrestrial behavior and habitat associations of post-metamorphic Taricha granulosa are poorly understood (Oliver and McCurdy 1974. Can. J. Zool. 52:541-545; Pimentel 1960. Amer. Midl. Nat. 63:470-496). Chandler (1918. Oregon Agric. Coll. Exper. Sta. Bull. 152:6) referenced Fall T granulosa aggregations in "cavities under stumps, logs, and stones," but does not present specific data...
Authors
Christopher A. Pearl

Spatial structure in the diet of imperial eagles Aquila heliaca in Kazakhstan Spatial structure in the diet of imperial eagles Aquila heliaca in Kazakhstan

We evaluated the relationship between spatial variability in prey and food habits of eastern imperial eagles Aquila heliaca at a 90,000 ha national nature reserve in north-central Kazakhstan. Eagle diet varied greatly within the population and the spatial structure of eagle diet within the population varied according to the scale of measurement. Patterns in dietary response were...
Authors
T.E. Katzner, E. A. Bragin, S.T. Knick, A.T. Smith

Do migratory flight paths of raptors follow constant geographical or geomagnetic courses? Do migratory flight paths of raptors follow constant geographical or geomagnetic courses?

We tested whether routes of raptors migrating over areas with homogeneous topography follow constant geomagnetic courses more or less closely than constant geographical courses. We analysed the routes taken over land of 45 individual raptors tracked by satellite-based radiotelemetry: 25 peregrine falcons, Falco peregrinus, on autumn migration between North and South America, and seven...
Authors
K. Thorup, M. Fuller, T. Alerstam, M. Hake, N. Kjellen, R. Strandberg

Juvenile salmonid use of freshwater emergent wetlands in the floodplain and its implications for conservation management Juvenile salmonid use of freshwater emergent wetlands in the floodplain and its implications for conservation management

A recent trend of enhancing freshwater emergent wetlands for waterfowl and other wildlife has raised concern about the effects of such measures on juvenile salmonids. We undertook this study to quantify the degree and extent of juvenile Pacific salmon Oncorhynchus spp. utilization of enhanced and unenhanced emergent wetlands within the floodplain of the lower Chehalis River, Washington...
Authors
Julie A. Henning, Robert E. Gresswell, Ian A. Fleming

Size dimorphism, molt status, and body mass variation of prairie falcons nesting in the Snake River Birds of Prey National Conservation Area Size dimorphism, molt status, and body mass variation of prairie falcons nesting in the Snake River Birds of Prey National Conservation Area

Thirty-nine bald eagles found sick or dead in 13 States during 1969 and 1970 were analyzed for pesticide residues. Residues of DDE, dieldrin, polychlorinated biphenyls (PCB's), and mercury were detected in all bald eagle carcasses; DDD residues were detected in 38; DDT, heptachlor epoxide, and dichlorobenzophenone (DCBP) were detected less frequently. Six eagles contained possible lethal...
Authors
Karen Steenhof, James O. McKinley
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