Northern Prairie Wildlife Research Center
Patterns of Prey Selection by Wolves
in Denali National Park, Alaska
by
L. David Mech, Thomas J. Meier, John W. Burch, and Layne G. Adams
The patterns of selection by wolves (Canis lupus) preying on moose
(Alces alces), caribou (Rangifer tarandus), and
Dall sheep (Ovis dalli) in Denali National Park and Preserve,
Alaska were studied from 1986 through early 1992. Wolves and their prey are
legally protected or relatively unharvested in most of the area, and wolf numbers
doubled during the study. Based on remains of 294 moose, 225 caribou, and 63
sheep, wolves killed calves and old adults disproportionately, and individuals
with low marrow fat, jaw necrosis, or arthritis. Seasonal trends in proportions
of various species, ages, and sex of kills were found. During the winters following
winters of deep snowfalls, wolves greatly increased the proportion of caribou
cows and calves taken. We conclude that in a natural system, wolves can survive
on vulnerable prey even during moderate weather, and when snowfall exceeds average,
they can respond by switching to newly vulnerable prey and greatly increasing
their numbers.
This resource is based on the following source (Northern Prairie Publication
LDM0144):
Mech, L. David, Thomas J. Meier, John W. Burch, and Layne G. Adams. 1995.
Patterns of prey selection by wolves in Denali National Park, Alaska.
Pages 231-244 in L.D. Carbyn, S.H. Fritts, and D.R. Seip, eds. Ecology
and Conservation of Wolves in a Changing World. Proceedings of the
Second North American Symposium on Wolves, Canadian Circumpolar
Institute, Edmonton, Alberta. Occasional Publication 35.
This resource should be cited as:
Mech, L. David, Thomas J. Meier, John W. Burch, and Layne G. Adams. 1995.
Patterns of prey selection by wolves in Denali National Park, Alaska.
Pages 231-244 in L.D. Carbyn, S.H. Fritts, and D.R. Seip, eds. Ecology
and Conservation of Wolves in a Changing World. Proceedings of the
Second North American Symposium on Wolves, Canadian Circumpolar
Institute, Edmonton, Alberta. Occasional Publication 35.
Jamestown, ND: Northern Prairie Wildlife Research Center Online.
http://www.npwrc.usgs.gov/resource/mammals/denali/index.htm
(Version 06JUL2000).
Table of Contents
Tables
- Table 1 -- Cumulative snowfall.
- Table 2 -- Composition of prey killed
by wolves.
- Table 3 -- Frequency of wolf kills.
- Table 4 -- Percent femur marrow fat content
of prey killed by wolves, October-May 1986-1991.
- Table 5 -- Percent femur marrow fat content
of prey killed by wolves, October-April 1988-1992.
- Table 6 -- Incidence of skeletal abnormalities
in prey killed by wolves.
Figures
- Figure 1 -- Annual proportions.
- Figure 2 -- Monthly proportions.
- Figure 3 -- Age structure of moose killed
by wolves.
- Figure 4 -- Age structure of caribou killed
by wolves.
- Figure 5 -- Age structure of Dall sheep
killed by wolves.
- Figure 6 -- Distributions of percent marrow
fat killed by wolves.
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denali.zip
(396K) -- Patterns of Prey Selection by Wolves in Denali National Park,
Alaska
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