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Page 5363, results 134051 - 134075

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Publication Extents

Not all publications have extents, not all extents are completely accurate
Birds
R.M. Erwin
1981, Book chapter, Conference on the coastal bays of Maryland and Virginia, Chincoteague, Sinepuxent and Assawoman, April 4, 1981
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
Methods of detecting and counting raptors: A review
M.R. Fuller, J. A. Mosher
C. John Ralph, J. Michael Scott, editor(s)
1981, Book chapter, Estimating Numbers of Terrestrial Birds
Most raptors are wide-ranging, secretive, and occur at relatively low densities. These factors, in conjunction with the nocturnal activity of owls, cause the counting of raptors by most standard census and survey efforts to be very time consuming and expensive. This paper reviews the most common methods of...
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...
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...
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...
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...
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...
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...