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Publications

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

Filter Total Items: 16758

Density estimation using the trapping web design: A geometric analysis Density estimation using the trapping web design: A geometric analysis

Population densities for small mammal and arthropod populations can be estimated using capture frequencies for a web of traps. A conceptually simple geometric analysis that avoid the need to estimate a point on a density function is proposed. This analysis incorporates data from the outermost rings of traps, explaining large capture frequencies in these rings rather than truncating them...
Authors
W.A. Link, R. J. Barker

Avian nesting success and diversity in conventionally and organically managed apple orchards Avian nesting success and diversity in conventionally and organically managed apple orchards

This study examines the effects of operational use of pesticides on avian species inhabiting apple orchards in Pennsylvania Mourning dove (Zenaida macroura) and American robin (Turdus migratorius) nests were monitored in three organic and three conventional apple orchards during 1990 and 1991 In 1991 we surveyed the avian communities of these orchards by using line transects...
Authors
K.M. Fluetsch, D. W. Sparling

Reproductive success of barn swallows nesting near a selenium-contaminated lake in east Texas, USA Reproductive success of barn swallows nesting near a selenium-contaminated lake in east Texas, USA

Reproductive success and contaminant levels in 1986 and 1987 were compared between Barn Swallows nesting at selenium-contaminated Martin Lake, Texas, USA, and swallows nesting at a reference site. Nests were initiated about the same time or earlier at Martin Lake than at the reference site and clutch size was similar between the two locations. Nest success was significantly higher at...
Authors
Kirk A. King, T. W. Custer, D.A. Weaver

Declines in organochlorines in eggs of red-breasted mergansers from Lake Michigan, 1977-78 versus 1990 Declines in organochlorines in eggs of red-breasted mergansers from Lake Michigan, 1977-78 versus 1990

From 1977–1978 to 1990, concentrations of polychlorinated biphenyls (PCBs) and most organochlorine pesticides declined in eggs of red-breasted mergansers (Mergus serrator) nesting on islands in northwestern Lake Michigan. Total PCBs decreased 60% (from 21 ppm in 1977–1978 to 8.5 ppm in 1990) and p,p′-DDE decreased 66% (from 6.5 to 2.2 ppm). Dieldrin decreased only 16% (from 0.82 to 0.69...
Authors
G. H. Heinz, D. S. Miller, B.J. Ebert, K. L. Stromborg

Puerto Rican parrots and potential limitations of the metapopulation approach to species conservation Puerto Rican parrots and potential limitations of the metapopulation approach to species conservation

Population viability analyses for a number of endangered species have incorporated a metapopulation approach. The risk assessments of these viability analyses have indicated that some extant populations should be subdivided into numerous subgroups with exchange of individuals among them in order to reduce the chance of catastrophic loss of the species. However, routine application of a...
Authors
Marcia H. Wilson, Cameron B. Kepler, Noel F.R. Snyder, Scott R. Derrickson, F. Josh Dein, James W. Wiley, Joseph M. Wunderle, Ariel E. Lugo, David L. Graham, William D. Toone

Range and habitats of the desert tortoise Range and habitats of the desert tortoise

We determined the current range of the desert tortoise (Gopherus agassizii) based on the available latest data from government agencies, the literature, and our experience. We developed the first detailed range map of this species and summarized information about habitat preferences. New records of occurrences were incorporated, and some peripheral localities of questionable authenticity...
Authors
D.J. Germano, R.B. Bury, T. C. Esque, T. H. Fritts
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