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Publications

Filter Total Items: 1990

Crater Lake: blue through time

Blue is the color of constancy, hence the term true blue. The unearthly blueness of Crater Lake reflects its pristine character and gives scientists a focal point for studying human impacts on aquatic environments over long periods of time. Scientists with the U.S. Geological Survey (USGS), National Park Service, and Oregon State University have systematically studied the lake for the last two
Authors
Gary L. Larson, Mark Buktenica, Robert Collier

Estimating population trends with a linear model

We describe a simple and robust method for estimating trends in population size. The method may be used with Breeding Bird Survey data, aerial surveys, point counts, or any other program of repeated surveys at permanent locations. Surveys need not be made at each location during each survey period. The method differs from most existing methods in being design based, rather than model based. The on
Authors
Jonathan Bart, Brian D. Collins, R. I. G. Morrison

Fire and amphibians in North America

Information on amphibian responses to fire and fuel reduction practices is critically needed due to potential declines of species and the prevalence of new, more intensive fire management practices in North American forests. The goals of this review are to summarize the known and potential effects of fire and fuels management on amphibians and their aquatic habitats, and to identify information ga
Authors
D. S. Pilliod, R.B. Bury, E.J. Hyde, C.A. Pearl, P. S. Corn

Impacts of the Brown Tree Snake: Patterns of Decline and Species Persistence in Guam's Avifauna

Predation by brown tree snakes (Boiga irregularis ) devastated the avifauna of Guam in the Mariana Islands during the last half of the twentieth century, causing the extirpation or serious reduction of most of the island's 25 resident bird species. Past studies have provided qualitative descriptions of the decline of native forest birds but have not considered all species or presented quantitative
Authors
G.J. Wiles, J. Bart, R.E. Beck, C.F. Aguon

Effects of soil amendments on germination and emergence of downy brome (Bromus tectorum) and Hilaria jamesii

Downy brome is an introduced Mediterranean annual grass that now dominates millions of hectares of western U.S. rangelands. The presence of this grass has eliminated many native species and accelerated wildfire cycles. The objective of this study was to identify soil additives that allowed germination but inhibited emergence of downy brome, while not affecting germination or emergence of the nativ
Authors
J. Belnap, S. K. Sherrod, M. E. Miller

Management implications of the ecology of free-roaming horses in semiarid ecosystems of the western United States

Compared to other ungulates of North America, free-roaming horses (Equus caballus) possess a unique evolutionary history that has given rise to a distinct suite of behavioral, morphological, and physiological traits. Because of their unique combination of cecal digestion, an elongate head with flexible lips, and non-uniform use of the landscape, horses represent a unique disturbance agent in semi-
Authors
Erik Beever

Osprey (Pandion haliaetus)

No abstract available.
Authors
C. J. Henny

The Killdeer (Charadrius vociferus)

No abstract available.
Authors
P.M. Sanzenbacher, Susan M. Haig

The Willet (Catoptrophorus semipalmatus)

No abstract available.
Authors
P.M. Sanzenbacher, Susan M. Haig

Peregrine Falcon (Falco peregrinus)

No abstract available.
Authors
C. J. Henny, J.E. Pagel