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Publications

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

Filter Total Items: 16718

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. David Mech, Nicholas E. Federoff

Sources of variation in survival and breeding site fidelity in three species of European ducks

1. We used long-term capture-recapture-recovery data and a modelling approach developed by Burnham (1993) to test a priori predictions about sources of variation in annual survival rates and fidelity within a population of individually marked females in three species of European ducks from a breeding ground study site in Latvia. 2. True annual survival was higher for diving ducks (tufted...
Authors
Peter Blums, James D. Nichols, James E. Hines

A new species of small-eared shrew from Colombia and Venezuela (Mammalia: Soricomorpha: Soricidae: Genus Cryptotis)

Populations of small-eared shrews inhabiting the northern Cordillera Oriental of Colombia and adjoining Venezuelan highlands in the vicinity of Paramo de Tama have been referred alternatively to Cryptotis thomssi or Cryptotis meridensis. Morphological and morphometrical study of this population indicates that it belongs to neither taxon, but represents a distinct, previously unrecognized...
Authors
Neal Woodman

Temporal variation in bird counts within a Hawaiian rainforest

We studied monthly and annual variation in density estimates of nine forest bird species along an elevational gradient in an east Maui rainforest. We conducted monthly variable circular-plot counts for 36 consecutive months along transects running downhill from timberline. Density estimates were compared by month, year, and station for all resident bird species with sizeable populations...
Authors
John C. Simon, T.K. Pratt, Kim E. Berlin, James R. Kowalsky, Steven G. Fancy, Jeff S. Hatfield

Species occurrence of marsh birds at Cape Cod National Seashore, Massachusetts

We initiated an inventory and a field test of a protocol that could be used for monitoring marsh birds at the Cape Cod National Seashore in eastern Massachusetts during 1999 and 2000, as part of a more comprehensive national effort. Using cassette tapes during call broadcast surveys, we visited a total of 78 survey points at freshwater, brackish, and salt marsh sites three times on the...
Authors
R.M. Erwin, C.J. Conway, S.J. Hadden

Declining pollinators and natural communities

No abstract available.
Authors
Howard S. Ginsberg

Wood Thrush movements and habitat use: Effects of forest management for Red-cockaded Woodpeckers

We monitored adult and juvenile breeding-season movements and habitat use of radio-tagged Wood Thrushes (Hylocichla mustelina) at the Piedmont National Wildlife Refuge, central Georgia, USA. We investigated the effects that management for Red-cockaded Woodpeckers (Picoides borealis), thinning and burning >30 year old loblolly pine (Pinus taeda) habitat, had on Wood Thrushes, a ground...
Authors
J. R. Lang, L.A. Powell, David G. Krementz, M.J. Conroy

Individual covariation in life-history traits: Seeing the trees despite the forest

We investigated the influence of age on survival and breeding rates in a long-lived species Rissa tridactyla using models with individual random effects permitting variation and covariation in fitness components among individuals. Differences in survival or breeding probabilities among individuals are substantial, and there was positive covariation between survival and breeding...
Authors
Emmanuelle Cam, William A. Link, E.G. Cooch, J. -Y. Monnat, Etienne Danchin

Variation in survivorship of a migratory songbird throughout its annual cycle

1. Demographic data from both breeding and non-breeding periods are needed to manage populations of migratory birds, many of which are declining in abundance and are of conservation concern. Although habitat associations, and to a lesser extent, reproductive biology, are known for many migratory species, few studies have measured survival rates of these birds at different parts of their...
Authors
Sillett T. Scott, Richard T. Holmes

Large scale wildlife monitoring studies: Statistical methods for design and analysis

Techniques for estimation of absolute abundance of wildlife populations have received a lot of attention in recent years. The statistical research has been focused on intensive small-scale studies. Recently, however, wildlife biologists have desired to study populations of animals at very large scales for monitoring purposes. Population indices are widely used in these extensive...
Authors
K. H. Pollock, James D. Nichols, T.R. Simons, G.L. Farnsworth, L.L. Bailey, John R. Sauer

On the estimation of species richness based on the accumulation of previously unrecorded species

Estimation of species richness of local communities has become an important topic in community ecology and monitoring. Investigators can seldom enumerate all the species present in the area of interest during sampling sessions. If the location of interest is sampled repeatedly within a short time period, the number of new species recorded is typically largest in the initial sample and...
Authors
Emmanuelle Cam, James D. Nichols, John R. Sauer, James E. Hines
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