Publications
These publications showcase the significant science conducted in our Science Centers.
Filter Total Items: 16731
α1-Antitrypsin polymorphism and systematics of eastern North American wolves α1-Antitrypsin polymorphism and systematics of eastern North American wolves
We used data on the polymorphic status of α1-antitrypsin (α1AT) to study the relationship of Minnesota wolves to the gray wolf (Canis lupus), which was thought to have evolved in Eurasia, and to red wolves (Canis rufus) and coyotes (Canis latrans), which putatively evolved in North America. Recent evidence had indicated that Minnesota wolves might be more closely related to red wolves...
Authors
L.D. Mech, N.E. Federoff
Leaf litter bags as an index to populations of northern two-lined salamanders (Eurycea bislineata) Leaf litter bags as an index to populations of northern two-lined salamanders (Eurycea bislineata)
Concern about recent amphibian declines has led to research on amphibian populations, but few statistically tested, standardized methods of counting amphibians exist. We tested whether counts of northern two-lined salamander larvae (Eurycea bislineata) sheltered in leaf litter bags--a relatively new, easily replicable survey technique--had a linear correlation to total number of larvae...
Authors
R.J. Chalmers, Sam Droege
A removal model for estimating detection probabilities from point-count surveys A removal model for estimating detection probabilities from point-count surveys
Use of point-count surveys is a popular method for collecting data on abundance and distribution of birds. However, analyses of such data often ignore potential differences in detection probability. We adapted a removal model to directly estimate detection probability during point-count surveys. The model assumes that singing frequency is a major factor influencing probability of...
Authors
G.L. Farnsworth, K. H. Pollock, J.D. Nichols, T.R. Simons, J.E. Hines, J.R. Sauer
The importance of functional form in optimal control solutions of problems in population dynamics The importance of functional form in optimal control solutions of problems in population dynamics
Optimal control theory is finding increased application in both theoretical and applied ecology, and it is a central element of adaptive resource management. One of the steps in an adaptive management process is to develop alternative models of system dynamics, models that are all reasonable in light of available data, but that differ substantially in their implications for optimal...
Authors
M.C. Runge, Fred A. Johnson
Royal Tern: Sterna maxima Royal Tern: Sterna maxima
No abstract available.
Authors
P. A. Buckley, F. G. Buckley
Forest restoration as ecological succession: should we speed it up or slow it down? Forest restoration as ecological succession: should we speed it up or slow it down?
Recent assessments of afforestation of agricultural lands in the Mississippi Alluvial Valley imply the importance of quickly developing vertical forest structure to benefit 'wildlife.' We examine this assumption and find that animal species of interest as targets of proactive management, as well as targets of control, occur through the full successional sere. Different species of mammals...
Authors
P.B. Hamel, D.J. Twedt, T.J. Nuttle, C.A. Woodson, F. Broerman, J.M. Wahome
Integrated management of waterbirds: Beyond the conventional Integrated management of waterbirds: Beyond the conventional
Integrated waterbird management over the past few decades has implicitly referred to methods for managing wetlands that usually attempt to enhance habitat for taxonomic groups such as shorebirds and wading birds, in addition to waterfowl, the traditional focus group. Here I describe five elements of integration in management: taxonomic, spatial, temporal, population and habitat, and...
Authors
R.M. Erwin
Assessment of stream quality using biological indices at selected sites in the Delaware River basin, Chester County, Pennsylvania, 1981-97 Assessment of stream quality using biological indices at selected sites in the Delaware River basin, Chester County, Pennsylvania, 1981-97
Introduction In 1970, the Chester County Water Resources Authority (Penn-sylvania) and the U.S. Geological Survey (USGS) established a long-term water-quality network with the goal of assessing the quality of streams in the county and understanding stream changes in response to urbanization using benthic-macroinvertebrate data. This database represents one of the longest continuous water...
Authors
Andrew G. Reif
Assessment of stream quality using biological indices at selected sites in the Big Elk and Octoraro Creek basins, Chester County, Pennsylvania, 1981-97 Assessment of stream quality using biological indices at selected sites in the Big Elk and Octoraro Creek basins, Chester County, Pennsylvania, 1981-97
Introduction In 1970, the Chester County Water Resources Authority (Pennsylvania) and the U.S. Geological Survey (USGS) established a long-term water-quality network with the goal of assessing the quality of streams in the county and understanding stream changes in response to urbanization using benthic-macroinvertebrate data. This database represents one of the longest continuous water...
Authors
Andrew G. Reif