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Publications

These publications showcase the significant science conducted in our Science Centers.

Filter Total Items: 16759

Calculation and error analysis of a digital elevation model of Hofsjokull, Iceland, from SAR interferometry Calculation and error analysis of a digital elevation model of Hofsjokull, Iceland, from SAR interferometry

Two ascending European Space Agency (ESA) Earth Resources Satellites (ERS)-1/-2 tandem-mode, synthetic aperture radar (SAR) pairs are used to calculate the surface elevation of Hofsjokull, an ice cap in central Iceland. The motion component of the interferometric phase is calculated using the 30 arc-second resolution USGS GTOPO30 global digital elevation product and one of the ERS tandem...
Authors
Jonathan S. Barton, Dorothy K. Hall, Oddur Sigurdsson, Richard S. Williams, Laurence C. Smith, James B. Garvin

Questions about Thayer's Gull Questions about Thayer's Gull

In response to recently published articles about the taxonomic status of Thayer's Gull, Larus thayeri, we pose several questions that should be answered before a taxonomic decision can be made.
Authors
Richard C. Banks, M.R. Browning

Metal and sediment ingestion by dabbling ducks Metal and sediment ingestion by dabbling ducks

The chemical analysis of intestinal digesta from hunter-killed carcasses or of wildlife scat is a promising means of estimating the exposure of wildlife to those environmental contaminants that, like lead, are poorly absorbed in the digestive tract. When evaluating contaminants at a site, biologists may find the results of this non-destructive approach more straightforward to interpret...
Authors
W. N. Beyer, J. Spann, Daniel D. Day

Fifty-eighth Christmas Bird Count. 166. Ocean City, Md Fifty-eighth Christmas Bird Count. 166. Ocean City, Md

Gauging the impact of manipulative activities, such as rehabilitation or management, on wetlands requires having a notion of the unmanipulated condition as a reference. An understanding of the reference condition requires knowledge of dominant factors influencing ecosystem processes and biological communities. In this paper, we focus on natural physical factors (conditions and processes)...
Authors
C.S. Robbins

Relative effects of plumage coloration and vegetation density on nest success Relative effects of plumage coloration and vegetation density on nest success

Many passerine species are highly dichromatic with brightly-colored males and cryptically-colored females. Bright plumage in males is commonly thought to arise as a result of sexual selection by females such that males with bright coloration possess high fitness. However, bright plumage potentially could expose males to increased predation risk. Consistent with this idea, males of many...
Authors
M.W. Miller

Marsh birds and the North American Breeding Bird Survey: judging the value of a landscape level survey for habitat specialist species with low detection rates Marsh birds and the North American Breeding Bird Survey: judging the value of a landscape level survey for habitat specialist species with low detection rates

The North American Breeding Bird Survey was started in 1966, and provides information on population change for >400 species of birds. it covers the continental United States, Canada, and Alaska, and is conducted once each year, in June, by volunteer observers. A 39.4 kIn roadside survey route is driven starting 30 min before sunrise, and a 3 min point count is conducted at each of 50...
Authors
J.R. Sauer

Responsiveness of gill Na+/K+-ATPase to cortisol is related to gill corticosteroid receptor concentrations in juvenile rainbow trout Responsiveness of gill Na+/K+-ATPase to cortisol is related to gill corticosteroid receptor concentrations in juvenile rainbow trout

A positive relationship between receptor concentration and tissue responsiveness is an often-assumed and rarely tested principle in endocrinology. In salmonids, seasonal changes in levels of plasma cortisol and gill corticosteroid receptors (CRs) during the spring indicate a potential role for this hormone in the parr–smolt transformation. It is not known whether these seasonal changes...
Authors
J. M. Shrimpton, S. D. McCormick
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