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Publications

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Supervised classification of Landsat thematic mapper imagery in a semi-arid rangeland by nonparametric discriminant analysis Supervised classification of Landsat thematic mapper imagery in a semi-arid rangeland by nonparametric discriminant analysis

In this article the authors used a nonparametric discriminant function in a supervised classification of Landsat Thematic Mapper satellite imagery of a ~240,000-ha semi-arid region in the Snake River Plains, southwestern Idaho. First, agriculture pixels were classified by distance from the soil baseline and water pixels by the thermal band value. Next, successive nonparametric...
Authors
Steven T. Knick, J.T. Rotenberry, T.J. Zarriello

Population identification of western hemisphere shorebirds throughout the annual cycle Population identification of western hemisphere shorebirds throughout the annual cycle

Identification of relationships among geographically distinct populations of migratory species can provide an understanding of breeding and natal philopatry, migration pathways, and population mixing during winter. We used random amplified polymorphic DNA (RAPD) analyses to search for markers specific to difficult‐to‐differentiate shorebird species (e.g. long‐billed dowitcher Limnodromus
Authors
Susan M. Haig, C. L. Gratto-Trevor, Thomas D. Mullins, M. A. Colwell

Spatial use and habitat selection of golden eagles in southwestern Idaho Spatial use and habitat selection of golden eagles in southwestern Idaho

We measured spatial use and habitat selection of radio-tagged Golden Eagles (Aquila chrysaetos) at eight to nine territories each year from 1992 to 1994 in the Snake River Birds of Prey National Conservation Area. Use of space did not vary between years or sexes, but did vary among seasons (home ranges and travel distances were larger during the nonbreeding than during the breeding...
Authors
J.M. Marzluff, Steven T. Knick, M.S. Vekasy, Linda S. Schueck, T.J. Zarriello

Productivity of golden eagles wearing backpack radiotransmitters Productivity of golden eagles wearing backpack radiotransmitters

We examined the association between the presence of backpack radiotransmitters and Golden Eagle (Aquila chrysaetos) reproduction (percentage of occupied territories producing young, and number of nestlings produced) over three years. The association between radio-tagging and nesting success and the number of nestlings produced varied significantly among years. A negative association with...
Authors
J.M. Marzluff, M.S. Vekasy, Michael N. Kochert, Karen Steenhof

Influence of basin-scale physical variables on life history characteristics of cutthroat trout in Yellowstone Lake Influence of basin-scale physical variables on life history characteristics of cutthroat trout in Yellowstone Lake

Individual spawning populations of Yellowstone cutthroat trout Oncorhynchus clarki bouvieri differ in life history characteristics associated with broad spatial and temporal environmental patterns, but relationships between specific life history characteristics of Yellowstone cutthroat trout and physical aspects of the environment are poorly understood. We examined basin-scale physical
Authors
Robert E. Gresswell, W.J. Liss, Gary L. Larson, Patrick J. Bartlein

The influence of habitat, prey abundance, sex, and breeding success on the ranging behavior of Prairie Falcons The influence of habitat, prey abundance, sex, and breeding success on the ranging behavior of Prairie Falcons

We studied the ranging behavior and habitat selection of radio-tagged Prairie Falcons (Falco mexicanus) during the breeding season in southwestern Idaho. The distribution and numbers of Townsend's ground squirrels (Spermophilus townsendii), the primary prey of Prairie Falcons in our study area, varied in response to drought during the study period. Prairie Falcons ranged over large areas...
Authors
J.M. Marzluff, Bryan A. Kimsey, Linda S. Schueck, Mary E. McFadzen, M.S. Vekasy, James C. Bednarz

Shorebird-prey interactions in South Carolina coastal soft-sediments Shorebird-prey interactions in South Carolina coastal soft-sediments

We investigated the simultaneous influence of benthic prey (primarily insect larvae, oligochaetes, and polychaetes) on spring-migrating shorebirds (Charadriiformes) and shorebirds on prey in brackish managed wetlands of South Carolina. We proposed that positive correlations between shorebird and prey densities and between prey reduction and shorebird density might result in a negative...
Authors
Louise M. Weber, Susan M. Haig

Use of burrow entrances to indicate densities of Townsend's ground squirrels Use of burrow entrances to indicate densities of Townsend's ground squirrels

Counts of burrow entrances have been positively correlated with densities of semi-fossorial rodents and used as an index of densities. We evaluated their effectiveness in indexing densities of Townsend's ground squirrels (Spermophilus townsendii) in the Snake River Birds of Prey National Conservation Area (SRBOPNCA), Idaho, by comparing burrow entrance densities to densities of ground...
Authors
Beatrice Van Horne, Robert L. Schooley, Steven T. Knick, Gail S. Olson, Kenneth P. Burnham

Nitrogen metabolism of sheep and goats consuming Acacia brevispica and Sesbania sesban Nitrogen metabolism of sheep and goats consuming Acacia brevispica and Sesbania sesban

We described the effects of two East African browses, Acacia brevispica and Sesbania sesban, on nitrogen metabolism of sheep and goats. The A. brevispica had a substantial amount of proanthocyanidins (condensed tannins); S. sesban did not. The browses were fed at three levels in combination with vetch (Vicia dasycarpa) and teff straw (Eragrostis abyssinica). Fecal N, N balance, and...
Authors
A. Woodward, J.D. Reed

Shorebird diet and size selection of nereid polychaetes in South Carolina coastal diked wetlands Shorebird diet and size selection of nereid polychaetes in South Carolina coastal diked wetlands

Coastal wetlands that are diked and managed may supplement declining natural habitat for migrating shorebirds (Charadriiformes). However, data on shorebird diet in these diked wetlands are scarce. We examined shorebird diet and prey size selection in brackish diked wetlands at the Yawkey Center on South Island, South Carolina, USA. Gut contents of seven Lesser Yellowlegs (Tringa flavipes...
Authors
Louise M. Weber, Susan M. Haig

Population structure of red-cockaded woodpeckers (Picoides borealis) in south Florida: RAPDs revisited Population structure of red-cockaded woodpeckers (Picoides borealis) in south Florida: RAPDs revisited

Six south Florida populations of the endangered red-cockaded woodpecker (Picoides borealis) were sampled to examine genetic diversity and population structure in the southernmost portion of the species' range relative to 14 previously sampled populations from throughout the species range. Random amplified polymorphic DNA (RAPD) analyses were used to evaluate the populations (n= 161...
Authors
Susan M. Haig, R. Bowman, Thomas D. Mullins

Effects of cutting time, stump height, parent tree characteristics, and harvest variables on development of bigleaf maple sprout clumps Effects of cutting time, stump height, parent tree characteristics, and harvest variables on development of bigleaf maple sprout clumps

In order to determine the effects of stump height, year of cutting, parent-tree size, logging damage, and deer browsing on bigleaf maple (Acer macrophyllum) sprout clump development, maple trees were cut to two stump heights at three different times. Stump height had the greatest impact on sprout clump size. Two years after clearcutting, the sprout clump volume for short stumps was...
Authors
J. C. Tappeiner, J. Zasada, D. Huffman, B. Maxwell
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