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Publications

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

Filter Total Items: 16780

Sexual Size Dimorphism in Hawks and Owls of North America

No abstract available.
Authors
N.F.R. Snyder, J. W. Wiley

American woodcock in West Virginia

No abstract available.
Authors
R.C. Kletzly

Trumpeter swan, Cygnus buccinator Richardson

No abstract available.
Authors
W.E. Banko, A.W. Schorger

Incidence of lead shot in canvasbacks

During 1975 and 1976, 2,544 canvasbacks (Aythya valisineria) from North Dakota, Wisconsin, Illinois, and Maryland were flouroscoped to determine the incidence of body shot. A significant increase from west to east was detected in the incidence of shot for immatures from the four states. The incidence of shot in immatures after the 1975-76 hunting season was 18 percent in Maryland and 20 percent
Authors
M. C. Perry

Chemical pollutants in field-collected canvasback tissues, eggs, and food materials

In 1972 studies began on the levels of environmental pollutants in canvasback tissues, eggs, and food items. The purpose of the studies were to determine if the levels of toxic chemicals found in canvasbacks were of the magnitude to cause problems affecting reproduction and survival. Overall, levels of organochlorine pesticides and PCB's were low in canvasbacks and their eggs. Some individual b
Authors
D. H. White, M. P. Dieter, R.C. Stendell

Preliminary assessment of aerial photography techniques for canvasback population analysis

Recent intensive research on the canvasback has focused attention on the need for more precise estimates of population parameters. During the 1972-75 period, various types of aerial photographing equipment were evaluated to determine the problems and potentials for employing these techniques in appraisals of canvasback populations. The equipment and procedures available for automated analysis of
Authors
R. E. Munro, D.L. Trauger

Comments on recent canvasback habitat trends and threats on Chesapeake Bay

During the last 22 years, the North American winter population of canvasbacks has fluctuated from 481,000 in 1955 to 179,000 in 1972. The Chesapeake Bay population has averaged 33 percent of the North American population and 64 percent of the Atlantic Flyway population. In Maryland, significant annual fluctuations have been recorded between the eastern and western shore of Chesapeake Bay. In 19
Authors
M. C. Perry