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Publications

Filter Total Items: 1990

Estimates of shorebird populations in North America

Estimates are presented for the population sizes of 53 species of Nearctic shorebirds occurring regularly in North America, plus four species that breed occasionally. Population estimates range from a few tens to several millions. Overall, population estimates most commonly fall in the range of hundreds of thousands, particularly the low hundreds of thousands; estimated population sizes for large
Authors
R. I. G. Morrison, Robert E. Gill, B. A. Harrington, S. K. Skagen, G. W. Page, C. L. Gratto-Trevor, S. M. Haig

Mountain hemlock growth responds to climatic variability at annual and decadal time scales

Improved understanding of tree growth responses to climate is needed to model and predict forest ecosystem responses to current and future climatic variability. We used dendroecological methods to study the effects of climatic variability on radial growth of a subalpine conifer, mountain hemlock (Tsuga mertensiana). Tree-ring chronologies were developed for 31 sites, spanning the latitudinal and e
Authors
D. W. Peterson, D. L. Peterson

Clutch sizes and nests of tailed frogs from the Olympic Peninsula, Washington

In the summers 1995-1998, we sampled 168 streams (1,714 in of randomly selected 1-m bands) to determine distribution and abundance of stream amphibians in Olympic National Park, Washington. We found six nests (two in one stream) of the tailed frog, compared to only two nests with clutch sizes reported earlier for coastal regions. This represents only one nest per 286 in searched and one nest p
Authors
R. Bruce Bury, P. Loafman, D. Rofkar, K. Mike

Habitat use by female caribou: Tradeoffs associated with parturition

We compared habitat use, forage characteristics, and group size among preparturient, parturient, and nonparturient female caribou (Rangifer tarandus) during and after the birthing season to test hypotheses involving acquisition of forage and risk of predation. We monitored 39 radiocollared females from the Mentasta caribou herd, Alaska, in 1994 and 40 animals in 1995. Group size of females giving
Authors
Neil L. Barten, R.T. Bowyer, Kurt J. Jenkins

Western pond turtles (Clemmys marmorata) in the central valley of California: Status and population structure

A sensitive resettable odometer reading to 0.01 mile facilitated censusing breeding male redwinged blackbirds (Agelaius phoeniceus) from a vehicle. Territorial males along roadsides were 'marked' with recorded mileage readings rather than with landmarks of the types employed by Hewitt for censuses based on the Lincoln index principle. Sensitive odometers that can be reset have many potential uses
Authors
David J. Germano, R. Bruce Bury

Changes in epiphyte communities as the shrub, Acer circinatum, develops and ages

The Pacific Northwest tall shrub Acer circinatum (vine maple) can host diverse and abundant epiphyte communities. A chronosequence approach revealed that these communities gradually shift in composition as the shrub progresses through its life cycle. Different epiphytic life forms occupy different spatial and temporal niches on shrub stems. These life forms generally shift upwards along the shrub
Authors
A.M. Ruchty, A.L. Rosso

Planned flooding and Colorado River riparian trade-offs downstream from Glen Canyon Dam, Arizona

Regulated river restoration through planned flooding involves trade-offs between aquatic and terrestrial components, between relict pre-dam and novel post-dam resources and processes, and between management of individual resources and ecosystem characteristics. We review the terrestrial (wetland and riparian) impacts of a 1274 m3/s test flood conducted by the U.S. Bureau of Reclamation in March/Ap
Authors
Lawrence E. Stevens, T.J. Ayers, J.B. Bennett, K. Christensen, M.J.C. Kearsley, V.J. Meretsky, A. M. Phillips, R.A. Parnell, J. Spence, M. K. Sogge, Abraham E. Springer, D.L. Wegner

Effects of exotic species on Yellowstone's grizzly bears

Humans have affected grizzly bears (Ursus arctos horribilis) by direct mortality, competition for space and resources, and introduction of exotic species. Exotic organisms that have affected grizzly bears in the Greater Yellowstone Area include common dandelion (Taraxacum officinale), nonnative clovers (Trifolium spp.), domesticated livestock, bovine brucellosis (Brucella abortus), lake trout (Sal
Authors
Daniel P. Reinhart, Mark A. Haroldson, D.J. Mattson, Kerry A. Gunther

Field soil aggregate stability kit for soil quality and rangeland health evaluations

Soil aggregate stability is widely recognized as a key indicator of soil quality and rangeland health. However, few standard methods exist for quantifying soil stability in the field. A stability kit is described which can be inexpensively and easily assembled with minimal tools. It permits up to 18 samples to be evaluated in less than 10 min and eliminates the need for transportation, minimizing
Authors
J. E. Herrick, W. G. Whitford, A. G. de Soyza, J. W. Van Zee, K. M. Havstad, C. A. Seybold, M. Walton

Winter distributions of North American Plovers in the Laguna Madre regions of Tamaulipas, Mexico and Texas, USA

To determine the distribution and abundance of wintering plovers in the Laguna Madre of Texas and Tamaulipas, surveys were conducted in December 1997 and February 1998, along a 160 km stretch of barrier islands in Mexico and- 40 km of shoreline on South Padre Island, Texas. Altogether, 5,673 individuals, representing six plover species, were recorded during the surveys. Black-bellied Plovers Pluvi
Authors
Todd J. Mabee, Jonathan H. Plissner, Susan M. Haig, J. P. Goossen

[Book Review] Diseases of Wild Waterfowl, by Gary A. Wobeser

Review of: Diseases of Wild Waterfowl. Gary A. Wobeser. 2nd Edition, illustrated. Springer, 1997. ISBN: 0306455900. 324 p.
Authors
Charles van Riper

Breeding bird response to juniper woodland expansion

In recent times, pinyon (Pinus spp.)-juniper (Juniperus spp.) woodlands have expanded into large portions of the Southwest historically occupied by grassland vegetation. From 1997-1998, we studied responses of breeding birds to one-seed juniper (J. monosperma) woodland expansion at 2 grassland study areas in northern Arizona. We sampled breeding birds in 3 successional stages along a grassland-woo
Authors
Steven S. Rosenstock, Charles van Riper