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Publications

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

Filter Total Items: 16785

Distribution and status of the peregrine falcon in South America

No abstract available.
Authors
J.W. McNutt, D. H. Ellis, C.P. Garat, T.B. Roundy, W.G. Vasina, C.M. White

Environmental contaminants and the management of bat populations in the United States

Food-chain residues of organochlorine pesticides probably have been involved in declines of some U.S. bat populations; examples include free-tailed bats at Carlsbad Cavern, New Mexico, and the endangered gray bat at sites in Missouri and Alabama. If a long-lived contaminant has not been dispersed in large amounts over large areas, its impact may be controlled by administrative action that stops i
Authors
D. R. Clark

Population estimates for the peregrine falcon in Arizona: A habitat inventory approach

At least 50 pairs of peregrine falcons reside in Arizona. From aerial surveys of available habitat and occupancy trends at more than 600 sites searched from 1975 to 1985, we estimated that at least 90 pairs resided in the study area. We project a fully recovered population of at least 190 pairs.
Authors
D. H. Ellis, R.L. Glinski

Foreword

No abstract available.
Authors
C.S. Robbins

An identifiable model for informative censoring

The usual model for censored survival analysis requires the assumption that censoring of observations arises only due to causes unrelated to the lifetime under consideration. It is easy to envision situations in which this assumption is unwarranted, and in which use of the Kaplan-Meier estimator and associated techniques will lead to unreliable analyses.
Authors
W. A. Link

Bias of animal population trend estimates

A computer simulation study of the population trend estimator used for the Mourning Dove Call-Count Survey, Woodcock Singing Ground Survey, Breeding Bird Survey and other surveys concluded that the estimator had negligible bias in most situations but that observer covariables should not be used with less than five years of data. With rare species (e.g. two birds per route), at least five years sh
Authors
P.H. Geissler, W. A. Link

Forest fragmentation and its effects on birds

Fragmentation of forest land, whether by suburban development, highways, transmission lines, or poorly planned cutting regimes, seriously affects reproduction by the large numbers of obligate forest interior birds. Many of our warblers, vireos, thrushes, tanagers, and flycatchers are highly migratory insectivorous birds that spend more than half the year in the neotropics, but migrate north to the
Authors
C.S. Robbins

Ferruginous hawk

In the Southwest, the ferruginous hawk is a local and isolated breeder and an uncommon but consistent winter visitor. Apparently, the breeding range of this species in the Southwest was historically much greater than today. The ferruginous hawk is being considered for listing by the U.S. Fish and Wildlife Service but remains unclassified by the individual states comprising the Southwest region. Ha
Authors
R.S. Hall, R.L. Glinski, D. H. Ellis, J.M. Ramakka, D.L. Base