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The ability to accurately age white-tailed deer facilitates evaluating management
strategies, monitoring population trends and herd health, and making management
decisions. Several years ago (Ag News and Views, April 1997), I reported results
from an ongoing study we were conducting on the Noble Foundation Wildlife Unit
(NFWU) on aging white-tailed deer using tooth eruption and wear patterns. This
technique was, and still is, the most frequently used field technique for aging
deer. Our data demonstrated limitations associated with the aging technique,
and we concluded that, based on tooth eruption and wear, we could confidently
place Noble Foundation Wildlife Unit deer into three age classes only
fawn, yearling and adult. To date, subsequent data collected on the NFWU support
this conclusion.
Our findings questioned the universal application of the technique for placing
adult deer into specific age classes, and we called for further evaluation of
the technique through the creation of known-age reference collections from other
parts of the country. I am happy to report that some other researchers are doing
just that. At the recent 26th Annual Meeting of the Southeast Deer Study Group,
Mickey Hellickson, a biologist with King Ranch, Inc., in south Texas, reported
on a reference collection they are establishing with more than 100 samples.
Their findings relative to tooth eruption and wear patterns are very similar
to ours, particularly in the 3.5 years and older age classes. As we found, there
was a strong tendency to under-age the older age-class animals based on tooth
wear. However, there is still no consistently applicable "fudge factor"
which can be used to increase the accuracy of the technique.
The tooth eruption and wear aging technique remains a useful tool in deer management,
when its limitations are recognized and used. In many management scenarios,
the ability to place deer into fawn, yearling, and adult age classes is sufficient
for making management decisions. Refinements of this technique and development
of different techniques are more likely as more reference collections are established
and evaluated.
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