Part 13

105 Adults 22 Fawns -- Sig., More female 95% fawns

Hunter-kills: Hunter-kills:

110 Field aged, 225 Field aged, Nonsig. Nonsig. -- 1967 1968

335 Field aged 98 Lab. aged Nonsig. Nonsig. --

132 Lab. aged, 79 Lab. aged, Nonsig. -- -- males females

89 Field aged, 246 Field aged, -- Sig., More male fawns adults 95% adults --------------------------------------------------------------------------- 433 Hunter-kills 142 Wolf-kills Sig., -- Older deer 99% in wolf-kill

321 Hunter-kills 118 Wolf-kills Sig., -- Older deer excluding excluding 99% in wolf-kill fawns fawns ---------------------------------------------------------------------------

FOOTNOTES:

Kolmogorov-Smirnov two-sample test (Siegel 1956).

Z test (Downie and Heath 1959).

Because test showed no significant differences in age or sex structure between sample of known wolf-kills and probable wolf-kills, these were combined for all subsequent tests and the pooled sample considered "wolf-kills."

At 95 percent level or greater. (NOTE: Lack of a significant difference does not prove that no difference exists. Rather, it means only that the available evidence does not allow the positive conclusion that a difference does exist.)

Wolf-kills found on lakes were compared with those located inland because of the possibility that kills on lakes may not be representative of kills in general.

Sample too small for test, but no apparent difference.

No significant difference in entire age structures. However, when the percentage of yearlings is compared between the two groups, the difference is almost significant at the 95 percent level.

Table 2.--Sex ratios of hunter-killed deer and wolf-killed deer from northeastern Minnesota

-------:--------------------------:------------------------- Age : Hunter-killed deer : Wolf-killed deer -------:--------------------------:------------------------- Number Percent Percent Number Percent Percent male female male female

Fawns 108 50 50 22 41 59 Adults 315 68 32 105 54 46 ------------------------------------------------------------

In the comparisons of the subsamples of hunter-kills, the only statistically significant difference found was that the adult subsample had a higher proportion of males than the fawn subsample. No significant difference was found in the age structures of the subsamples, so these were all pooled into a sample of 433 hunter-kills for comparison with the wolf-kills. For the same reason, the entire sample of 142 wolf-killed deer was used for a comparison with the hunter-killed sample.

Table 3.--Sex ratios of wolf-killed deer from wilderness areas and from hunted areas

#: Number %: percent

-------:-------------------:------------------:----------------- Age : Wilderness area : Hunted area : Total -------:-------------------:------------------:----------------- # % % # % % # % % male female male female male female

Fawns 4 0 100 18 50 50 22 41 59 Adults 41 71 29 64 44 56 105 56 44 ----------------------------------------------------------------

Wolf-killed deer in our sample, with an average age of 4.7 years, were significantly older (99 percent level) than hunter-killed deer, with an average age of 2.6 years. For example, deer 5 years of age and older made up 48 percent of the wolf-kills but only 10 percent of the hunter-kills (table 4). The oldest hunter-killed deer in our sample was 9-1/2 years old, but the oldest wolf-killed deer was 14-1/2 (fig. 7).

Because of a possible bias against fawns in the method of collecting data from wolf-kills (to be discussed later), the age structure of the sample of wolf-kills excluding fawns was tested against that of the sample of hunter-kills excluding fawns. The result once again was a highly significant difference between these two age structures (table 1).

As an additional test of the degree to which the age structure of the wolf-killed deer might differ from that of the actual population, we compared our wolf-kill age structure with the age structure of a hypothetical deer population. This was considered advisable just in case the hunter-kill data were poorly representative of the age structure of the actual deer herd. Several hypothetical age structures were constructed and compared according to advice from Downing. In all cases, the comparisons produced the same basic results as the tests with the hunter-killed sample. An example of one comparison is given in figure 7.

A further result obtained by aging the wolf-killed deer pertained to the young individuals killed. The deciduous first incisors of fawns and the deciduous premolars of yearlings are usually replaced with permanent teeth by December (Severinghaus 1949). Of 24 wolf-killed fawns examined, however, three (13 percent) taken during January, February, and March had not yet replaced their deciduous first incisors. Of the 13 yearlings found during this same period, nine (70 percent) had failed to replace their deciduous premolars, and two (15 percent) had just replaced them (one deer killed in February and one killed in March).

FOOTNOTES: