Censusing wolves in a 1.5-million-acre study area is a difficult task,
and we have no direct information on which to base a population
estimate. However, some deductions can be made about the relative
population densities in our study area between the period 1948 to 1953
and the period of the present study, 1967 to 1969.
R. A. Rausch (1967a) hypothesized that the frequency of large packs is
higher when population density is high, and presented evidence
supporting this idea. On this assumption, a comparison of pack-size
distributions between various periods can indicate relative population
densities between periods. The advantage of this method is that it
eliminates the usual type of year-to-year biases in wolf censuses such
as might result from differences in precise census route, type of
aircraft, skill of observers, and other conditions. Only a difference
that would cause a bias in the _size_ of the packs seen would be of
importance.
Therefore, we tested the difference in size distributions of population
units between the 1948-53 study period and the present period (table
1), using a Kolmogorov-Smirnov two-sample test (Siegel 1956). The
average "pack" size in the earlier years was 2.8, compared with 4.2 at
present; thus pack sizes are significantly larger at present (95
percent level). This indicates that the population density from 1967 to
1969 may have been higher than from 1948 to 1953. This apparent change
may be attributable to a reduction in snaring, trapping, and aerial
hunting that took place between the two periods as a result of changes
in State game regulations.
A similar comparison between our observations from 1967 and those from
1968-69 (table 1) shows no significant difference between these years,
so it appears that the density of wolves in our area has remained about
the same over the period of three winters. This agrees with the results
of several other studies summarized by Mech (1970) in which wolf
populations unaffected by man have been found to remain relatively
stable from year to year.