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Deer hunters who hold to the belief that the biggest, baddest bucks dominate the breeding season and sire next year’s crop of fawns are in for a shock when they learn that new DNA research says it isn’t so.

A study published in the August issue of the Journal of Mammology notes that among white-tailed deer, every buck has a chance to contribute to the next generation.

Prior studies, often relying too heavily on behavioral observations and circumstantial evidence, typically characterized male reproductive success as highly skewed toward a small number of mature, dominant bucks that monopolize the breeding.

But six researchers, led by Randy DeYoung, of Mississippi State University, have shown otherwise. They found, in DNA analysis of 1,219 deer, that physically immature bucks 1½ to 2½ years old fathered 30 to 33 percent of the fawns in the three populations they examined. And that held even when larger, mature males were at hand.

Thus, the researchers concluded, social dominance alone may not guarantee reproductive success.

The deer they tested came from three locations — Noxubee National Wildlife Refuge in Mississippi, the King Ranch in Texas, and the Noble Foundation Wildlife Unit in Oklahoma.

Because of long-term differences in the management of harvesting the deer — one site allowed public hunting while another placed conservative restrictions on thinning the herd — each of the herds had differing make-up and that allowed for a high-quality evaluation of factors such as herd sex-ratio and age-structure among the bucks. In short, they looked at a broad range of possibilities, which makes for sound science.

“It’s really interesting stuff,” summed Mike Tonkovich, the highly regarded deer biologist with the Ohio Division of Wildlife. “This genetic research crushes our thinking on how whitetails do their breeding.”

The Buckeye biologist cited research as recent as 1995 and even later that supports the notion the big boys among the bucks do the breeding.

He added he personally knows five of the six scientists in this ground-breaking research and their work is solid. The journal in which they are published is highly respected and rigorously watched by peers.

“The technology has come so far,” asserted Tonkovich after reading the journal report. “It is answering a lot of questions.

“What amazes me most is that we really believed for the longest time that there were a few dominant bucks that did most of the breeding.”

He said such a contention really does not make sense. It is known, for example, that during the breeding season or rut that a buck “tends” a given doe exclusively for 24 to 36 hours. Which begs the question about how can they manage to impregnate most of the herd when there are so many does and so little time — and relatively so few mature bucks.

Tonkovich said the window of opportunity for breeding in a well-managed deer herd, such as Ohio’s, is fairly narrow. Here the majority of breeding occurs in November, for example. When you think about that and the vast statewide distribution of deer, the biologist said, the older notion about breeding suddenly becomes improbable.

He said an amazing 25 percent of multiple fawns birthed by a doe were found to be sired by different bucks. “The peak of the rut is a free-for-all,” the biologist said.

Off peak, the mature bucks may dominate, he acknowledged.

In any case, whitetail bucks are not bull elk, which may defend and try to tend a harem of 20 or 30 cows.

None of which is to deny that competition and fighting among bucks occurs during the rut.

But it now is hard to contend that winning a sparring match means breeding dominance.

“We can only speculate what deer behavior was like before European settlement,” the biologist noted. In other words, we do not know and cannot know how deer behaved in a totally natural environment unaffected by man-induced changes.

“From a practical standpoint, from what we know now, most bucks have an opportunity to pass genes to the next generation. It raises the question of whether trying to manage genetics by harvesting based on antler characteristics is a waste of time.”

Thus it may be futile to try to protect a single buck with the thought of dominating a future gene pool. The wiser plan, Tonkovich added, is to “just get the right number of deer on the land.”

Contact Steve Pollick at:spollick@theblade.comor 419-724-6068.

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