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Publications

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

Filter Total Items: 16731

Effect of restrictive harvest regulations on survival and recovery rates of American black ducks Effect of restrictive harvest regulations on survival and recovery rates of American black ducks

Population management of waterfowl requires an understanding of the effects of changes in hunting regulations on harvest and survival rates. Mean survival and recovery rates of American black ducks (Anas rubripes) were estimated during 3 periods of increasingly restrictive harvest regulations: 1950-66, 1967-82, and 1983-93. From the first to the second period, direct recovery rates...
Authors
C.M. Francis, J.R. Sauer, J.R. Serie

Assemblage organization in stream fishes: Effects of environmental variation and interspecific interactions Assemblage organization in stream fishes: Effects of environmental variation and interspecific interactions

We assessed the relative importance of environmental variation, interspecific competition for space, and predator abundance on assemblage structure and microhabitat use in a stream fish assemblage inhabiting Coweeta Creek, North Carolina, USA. Our study encompassed a 10–yr time span (1983–1992) and included some of the highest and lowest flows in the last 58 years. We collected 16...
Authors
Gary D. Grossman, R. E. Ratajczak, M. M. Crawford, Mary C. Freeman

Mercury in alligators (Alligator mississippiensis) in the southeastern United States Mercury in alligators (Alligator mississippiensis) in the southeastern United States

Mercury methylation may be enhanced in wetlands and humic-rich, blackwater systems that crocodiles and alligators typically inhabit. Given their high trophic level and long life-spans, crocodilians could accumulate significant burdens of Hg. Our objectives were to survey Hg concentrations in alligators from several areas in the southeastern United States to test their utility as...
Authors
C. H. Jagoe, B. Arnold-Hill, G. M. Yanochko, P. V. Winger, I. L. Brisbin

Cranial and dental abnormalities of the endangered red wolf Canis rufus Cranial and dental abnormalities of the endangered red wolf Canis rufus

Three skulls of captive-raised female endangered red wolves (Canis rufus) exhibited severe malocclusion of the jaws. Cranial and dental abnormalities (including crowding of upper toothrows, and an extra tooth behind the lower left M3 in one of the three mandibles) were also evident. Ratios of alveolar length of maxillary toothrow to maximum width across the outer sides of crowns of P4...
Authors
Nicholas E. Federoff, Ronald M. Nowak

Use of a helicopter to capture flighted cranes Use of a helicopter to capture flighted cranes

Using a helicopter, we pursued 12 sandhill cranes (Grus canadensis) and captured 6. In forested habitat, cranes could be forced down, but we were unable to deploy the pursuit team, so cranes could not be captured. In open habitat, every crane we pursued was captured. Target cranes were forced to the ground in 0.3-14 minutes. Adjusting pursuit distance (50-150 m) was essential in...
Authors
D. H. Ellis, D. Hjertaas, B.W. Johns, R.P. Urbanek

The response of primary producers to nutrient enrichment in a shallow estuary The response of primary producers to nutrient enrichment in a shallow estuary

Shallow coastal systems worldwide are exhibiting increased algal growth in response to nutrient enrichment. This study evaluates primary production patterns in an estuarine system (Bass Harbor Marsh, Maine) receiving low levels of anthropogenic nitrogen. Biomass, areal coverage and in situ oxygen production of green macroalgae, Ruppia maritima, and phytoplankton were measured over a...
Authors
E.H. Kinney, C. T. Roman

Changing number of Canada geese wintering in different regions of the Atlantic Flyway Changing number of Canada geese wintering in different regions of the Atlantic Flyway

During the past 40 years, profound changes have occurred in the number of Canada geese (Branta canadensis) wintering in different regions of the Atlantic Flyway. To explain the declining number of wintering geese in the Chesapeake and Carolina regions and the increasing number in the mid-Atlantic region from 1984 to 1989, I tested several hypotheses concerning regional differences in...
Authors
J.B. Hestbeck

The Wisconsin Frog and Toad Survey: Update and 1984-97 trends [abstract] The Wisconsin Frog and Toad Survey: Update and 1984-97 trends [abstract]

The Wisconsin Frog and Toad Survey (WFTS) is a volunteer-based, roadside auditory count that began in 1981. It's protocols were recently modified for continent-wide use by the North American Amphibian Monitoring Plan (NAAMP). In 1997 we initiated a study to compare data collected by the WFTS and NAAMP protocols, in order to guide WFTS transition from its current methodology to one more...
Authors
M.J. Mossman, L. Hartman, J. Sauer, R. Hay, B. Dhuey
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