SANDESTIN, Fla. – If you’re a Great Lakes States bowhunter who blames every apparent deer shortage on predators, be thankful you don’t hunt parts of the Southeastern United States. Coyotes in some Southeastern regions prey so heavily on newborn whitetails that less than one in five fawns lives four months.
And if you’re a Great Lakes wildlife biologist discussing predators with your colleagues, ask yourself the last time one of them told you to “Get with it!” or “Get your head out of (long pause) the sand” in public.
Well, many wildlife managers talked that way a few weeks ago at the 35th annual Southeast Deer Study Group meeting, which attracted about 325 deer biologists and researchers from universities, wildlife agencies, and timber companies across the South and northward. I’ve been attending this annual gathering since 1991 because it’s a great source for the latest research on white-tailed deer.
In some parts of the whitetail’s Southeastern range, many fawns don’t live to see their third month.
“My guess is that the skeptics haven’t yet seen places that once had deer but don’t anymore. The data we collected at the Savannah River Site (South Carolina) showed it took a 75 percent harvest reduction by hunters to level the population decline. Also, preliminary research doesn’t show much promise for mitigating coyote impacts on deer by improving and expanding fawning cover, or increasing buffer foods.”
Ten years ago, most Southeastern biologists never thought they’d be worrying about coyotes, which aren’t native to the region. But as coyotes moved in the past 30 years, they adapted, reproduced, and learned newborn fawns were easy prey.
Coyotes can kill deer in winter, but do most of their predation when fawns are less than a week old.
“Coyotes are increasing at rates that remind me of what our deer herds did in the 1980s and ’90s,” said Dr. Charles Ruth, deer project supervisor for South Carolina’s Department of Natural Resources. “When I talked to folks 10 years ago, I often said if I could get my foot on our deer herd, I would pull out my knife. Well, I’m kind of having to chill out on that approach.”
Perhaps the most fascinating aspect of predator-deer impacts is their wide variability within regions and states. When Kilgo reviewed pre-2005 predation studies across the United States, he found coyote-inflicted mortality on deer averaged 16 percent in Northern states and 44 percent in Southern states.
Black bears killed more fawns than coyotes did in a Wisconsin study.
“The North’s highest mortality rate was 38 percent,” he said. “That doesn’t even reach the South’s average,” he said.
But it’s not consistent across the South, either. A 2008-2011 study on northern Virginia’s Quantico Marine Corps base found 60 percent of fawns lived past three months, and more died of natural causes, 53 percent, than predation, 18 percent.
But in 2011, in the first year of a study at the Fort Bragg Military Institution in North Carolina, researchers reported only five of 27 fawns (18.5 percent) survived their first four months, with 15 of the 22 dead fawns (68 percent) killed by coyotes or bobcats.
How do those studies compare to similar research by the Wisconsin DNR? To refresh, one study site is a 3,500-square mile Northern-forest setting in Sawyer, Price and Rusk counties. The other is a 2,300-square mile east-central farmland setting in Shawano, Waupaca and Outagamie counties.
A Michigan study is finding coyotes to be the whitetail’s No. 1 predation risk.
During the first year (2011) of Wisconsin’s Northern study, 27 percent of ID-tagged fawns (eight of 30) survived seven months, with 17 of 30 (57 percent) killed by predators. Five others died of starvation or other causes. The top predator was black bears, with five fawn kills. Unknown predators killed four; hunters, three; bobcats, two; unknown canid, two; and coyote, one.
For perspective, a 1973-1983 study in Minnesota’s northeastern forests found annual fawn survival was 31 percent, not significantly better.
But in the first year of Wisconsin’s east-central farmland study, 62.5 percent of ID-tagged fawns (30 of 48) survived seven months, with eight of the 18 deaths (44 percent) caused by predators. The others died of starvation, six (33 percent); vehicle collisions, three (16.5 percent); and unknown causes, one. The top predator was coyotes, with four fawn kills. Hunters killed two; black bears, one; and unknown, one.
Meanwhile, researchers in Michigan’s south-central Upper Peninsula estimated fawn survival at 37 percent in January 2011after two years of study in Menominee County. With three years of data now in, researchers report 47 of their ID-tagged fawns were killed by four-legged predators.
Coyotes killed 22 fawns (47 percent of kills), followed by bobcats, 12 (25.5 percent), unknown predators, five (11 percent), black bears, four (8.5 percent) and wolves, four (8.5 percent).
What to make of all this? Few hunters or biologists will find much comfort or scientific certainty in such varying, ever-changing numbers.