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Publications

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

Filter Total Items: 16785

Relationship of deer and moose populations to previous winters' snow

(1) Linear regression was used to relate snow accumulation during single and consecutive winters with white-tailed deer (Odocoileus virginianus) fawn:doe ratios, moose (Alces alces) twinning rates and calf:cow ratios, and annual changes in deer and moose populations. Significant relationships were found between snow accumulation during individual winters and these dependent variables during the fo
Authors
L. D. Mech, R.E. McRoberts, R. O. Peterson, R.E. Page

Use of urine in snow to indicate condition of wolves

Urine deposited in snow by wild gray wolves (Canis lupus) and by fed and fasted captive wolves was analyzed for urea nitrogen, calcium, sodium, potassium, and creatinine. Ratios of the elements with creatinine were considerably higher for fed than for fasted animals, and ratios for fed wolves compared favorably with ratios from wolf urine in snow along trails leading from kills. Thus, wolf urine i
Authors
L. D. Mech, U. S. Seal, G. D. DelGiudice

Ecology, behavior, and conservation of the Maui parrotbill

The distribution, habitat response, sexual dimorphism, foraging, breeding, and flocking behavior of Maui Parrotbills (Pseudonestor xanthophrys ) were studied over a five year period. The species' present range is confined to montane rainforest on eastern Maui, but dry lowland habitats on Maui and Molokai were occupied before Polynesian contact. Birds occurred from 1,250 to 2,150 m elevation, becom
Authors
S. Mountainspring

Nest-box use by prothonotary warblers (Protonotaria citrea) in riverine habitat

No abstract available.
Authors
L. J. Petit, W. J. Fleming, K.E. Petit, D. R. Petit

Some aspects of the breeding biology of the snail kite in Florida

The breeding biology of the Snail Kite was studied in Florida from 1968-1977 and intermittently from 1978-1980. Breeding occurred every month, but not in the same year. Peak egg-laying occurred from February through April or generally about 8 1 d before the onset of the rainy season in mid- or late May. Courtship displays, copulation and duration of copulation are described. Mean egg-laying inter
Authors
P.W. Sykes

Blastomycosis in wild wolves

Blastomycosis was fatal to a wild wolf in Minnesota, and serologic evidence of blastomycosis was found in a Wisconsin wolf. No unusual movements were detected in the Minnesota animal from October 1983 through October 1985. However, by early December 1985, this wolf was weak and debilitated, and it perished on 14 December after approaching a human residence.
Authors
Richard P. Thiel, L. David Mech, George R. Ruth, John R. Archer, Leo Kaufman

Cave gate designs for use in protecting endangered bats

No abstract available.
Authors
D. H. White, J.T. Seginak

Propagation of captive eastern screech-owls

No abstract available.
Authors
Stanley N. Wiemeyer

Frequency sampling in microhistological studies: An alternative model

Frequency sampling in microhistological studies is discussed in terms of sampling procedures, statistical properties, and biological inferences. Two sampling approaches are described and contrasted, and some standard methods for improving the stability of density estimators are discussed. Possible sources of difficulty are highlighted in terms of sampling design and statistical analysis. An altern
Authors
B.K. Williams

Primary molt of California condors

Primary molt of the California Condor (Gymnogyps californianus) was studied intensively from 1982 through 1985, using repeated flight photographs of the remaining individuals in the wild population as a basis for most analyses. On the average, wild condors replaced 4.4 of the 8 emarginated primaries on each wing each year. The sepcific primaries molted were generally the ones missed in the previou
Authors
N.F.R. Snyder, E.V. Johnson, D.A. Clendenen