The effect of use limits on backcountry visitation trends in Yosemite National Park
J. W. van Wagtendonk
1981, Leisure Science (4) 311-323
Backcountry use in Yosemite National Park increased drastically during the decade starting in the mid 1960s. In 1975, use reached a maximum of nearly 79,000 visitors and 219,000 visitor nights. Since then use has leveled off to about 89 percent of the peak figures for visitors and 84 percent for...
Summary of foreign gamebird liberations 1969-1978
R.C. Banks
1981, Special Scientific Report - Wildlife 239
Effects of highways on wildlife
L.W. Adams, A. D. Geis
1981, Report FHWA/RD-81/067
Pilot study of the marine mammals, birds and turtles in OCS areas of the Gulf of Mexico
T. H. Fritts, R.P. Reynolds
1981, FWS/OBS 81/36
Effects of petroleum on the development and survival of marine turtle embryos
T. H. Fritts, M.A. McGehee
1981, FWS/OBS 81/37
Estimating Numbers of Terrestrial Birds
1981, Studies in Avian Biology
Texas barrier island region ecological characterization: environmental synthesis papers
D.M. Shew, R.H. Baumann, T. H. Fritts, L.S. Dunn
1981, FWS/OBS 81/32
Dynamics, movements, and feeding ecology of a newly protected wolf population in northwestern Minnesota
Steven H. Fritts, L. David Mech
1981, Book, Wildlife Monographs
No abstract available....
Deer social organization and wolf predation in northeastern Minnesota
Michael E. Nelson, L. David Mech
1981, Book, Wildlife Monographs
No abstract available....
Marking ground targets with radio transmitters dropped from aircraft
T.H. Nicholls, M.E. Ostry, M.R. Fuller
1981, Research Note NC-274
Newsletter for the Accelerated Research Program for migratory shore and upland game birds
R.A. Coon
1981, Newsletter for the Accelerated Research Program for migratory shore and upland game birds No. 6.
Birds
R.M. Erwin
1981, Book chapter, Conference on the coastal bays of Maryland and Virginia, Chincoteague, Sinepuxent and Assawoman, April 4, 1981
Physical and chemical characteristics of warmwater streams: A review
P. V. Winger
Louis A. Krumholz, editor(s)
1981, Book chapter, The Warmwater Streams Symposium: a national symposium on fisheries aspects of warmwater streams : proceedings of a symposium held at the University of Tennessee, Knoxville, Knoxville, Tennessee, 9-11 March, 1980
The whooping crane
R.C. Erickson, S.R. Derrickson
James C. Lewis, Hiroyuki Masatomi, editor(s)
1981, Book chapter, Crane Research Around the World: Proceedings of the International Crane Symposium
The North American Breeding Bird Survey
D. Bystrak
C. John Ralph, J. Michael Scott, editor(s)
1981, Book chapter, Estimating Numbers of Terrestrial Birds
A brief history of the North American Breeding Bird Survey (BBS) and a discussion of the technique are presented. The approximately 2000 random roadside routes conducted yearly during the breeding season throughout North America produce an enormous bank of data on distribution and abundance of breeding birds with great potential...
Neoplasia and other disease problems in black-footed ferrets: Implications for an endangered species
J. W. Carpenter, M.N. Novilla, H.E. Kaiser
Hans E. Kaiser, editor(s)
1981, Book chapter, Neoplasms--Comparative pathology of Growth in Animals, Plants, and Man
A funding source for sandhill crane research: The Accelerated Research Program for Migratory Shore and Upland Game Birds
R.A. Coon, T.J. Dwyer
J. C. Lewis, editor(s)
1981, Book chapter, Proceedings of the 1981 Crane Workshop
Management and research opportunities with urban wildlife
A. D. Geis
Ron R. Odom, J.W. Guthrie, editor(s)
1981, Book chapter, Proceedings of the Nongame and Endangered Wildlife Symposium, August 13-14, 1981, Athens, Georgia
Roads and roadside habitat in relation to small mammal distribution and abundance
L.W. Adams, A. D. Geis
R.E. Tillman, editor(s)
1981, Book chapter, Environmental Concerns in Rights-of-Way Management. Proceedings of Second Symposium
The role of observer bias in the North American Breeding Bird Survey
C. A. Faanes, D. Bystrak
1981, Book chapter, Estimating Numbers of Terrestrial Birds
Ornithologists sampling breeding bird populations are subject to a number of biases in bird recognition and identification. Using Breeding Bird Survey data, these biases are examined qualitatively and quantitatively, and their effects on counts are evaluated. Differences in hearing ability and degree of expertise are the major observer biases...
Sampling in rugged terrain
D.K. Dawson
C. John Ralph, J. Michael Scott, editor(s)
1981, Book chapter, Estimating Numbers of Terrestrial Birds
Work in rugged terrain poses some unique problems that should be considered before research is initiated. Besides the obvious physical difficulties of crossing uneven terrain, topography can influence the bird species? composition of a forest and the observer's ability to detect birds and estimate distances. Census results can also be...
Metals and terrestrial earthworms (Annelida: Oligochaeta)
W. N. Beyer
1981, Book chapter, Workshop on the Role of Earthworms in the Stabilization of Organic Residues, Proceedings, Volume 1.
The toxicity of metals to earthworms and the residues of metals found in earthworms are reviewed. Meta 1 concentrations are rarely high enough to be toxic to worms, but copper may reduce populations in orchards heavily treated with fungicides and in soil contaminated with pig wastes. The metals in some...
Estimates of avian population trends from the North American Breeding Bird Survey
P.H. Geissler, B.R. Noon
C. John Ralph, J. Michael Scott, editor(s)
1981, Book chapter, Estimating Numbers of Terrestrial Birds
One of the major purposes of bird population studies is to document changes in population size over a period of years. The traditional method used in Europe and North America to detect population change is to calculate annual ratios. However, this method can produce spurious results when ratios...
Interpreting population estimates of birds following pesticide applications--behavior of male starlings exposed to an organophosphate pesticide
C.E. Grue, B.J. Shipley
C. John Ralph, J. Michael Scott, editor(s)
1981, Book chapter, Estimating Numbers of Terrestrial Birds
We determined activity budgets for 10 pairs of captive male Starlings between 7 May and 18 July 1980. Our objective was to quantify changes in behavior after exposure to an organophosphate (OP) pesticide and to assess the impact of changes in behavior on the interpretation of population estimates of birds...
Effects of forest fragmentation on avifauna of the eastern deciduous forest
R.F. Whitcomb, C.S. Robbins, J.F. Lynch, B.L. Whitcomb, M. K. Klimkiewicz, D. Bystrak
Robert L. Burgess, David M. Sharpe, editor(s)
1981, Book chapter, Forest Island Dynamics in Man-Dominated Landscapes
