Can’t help pondering fawns and predators
For years, folks who have voiced fears and strident warnings about the impact of predators on Pennsylvania’s deer fawns have been widely regarded as kooks and cranks.
But a study unfolding in the Upper Peninsula of Michigan makes me wonder.
Before I proceed any further, I want to, as they say in a court of law, stipulate to two Keystone State realities:
- Fawns here have about a 1-in-2 chance of surviving to their first birthday. That sounds morbid, but that’s a little better than in much of the whitetail’s range.
- Hunter harvest data, compiled by the Game Commission, shows that the percentage of fawns in the hunter harvest has remained stable for a long time, and shows no signs of being reduced by increased predation.
Still, the Michigan research -- which is intended to assess the impact of wolves on the deer population -- is thought-provoking, to say the least. But I have no idea what it might mean in Pennsylvania, let alone for the Upper Peninsula.
Many Michigan hunters thought the estimated 687 gray wolves that live in the Upper Peninsula -- where the whitetail population has sagged -- were eating most of the deer fawns.
But researchers found this past winter, the third year of a deer-mortality study, that coyotes were the No. 1 predator followed by bobcats. Wolves came in fourth after a three-way tie between hunters, unknown predators and unknown causes.
“I was somewhat surprised to see coyotes play as large a role in fawn predation as they did,” said Jerry Belant, an associate professor of wildlife ecology at Mississippi State University. Belant oversees student researchers who are working in partnership with the Michigan Department of Natural Resources.
Researchers got their data from 142 fawns fitted with GPS collars. The devices transmitted their location every 15 minutes. Eighty collared fawns died during the three-year first phase of the study. Predators killed 73 percent of those fawns.
The situation in the Upper Peninsula -- where deep snow and brutal winters can decimate the deer herd -- may not really have much relevance to Pennsylvania. But I thought it was surprising that scientists there found bobcats to be such efficient fawn killers.
Here, we have been led to believe that bobcats don’t bother much with deer. I wonder what this means, with our newly resurgent bobcat population that is now substantial enough to be hunted and trapped in much of the state.
And in the Upper Peninsula, they did not find much evidence of fawn predation by black bears, although perhaps bruins represent the “unknown predators” in the Michigan study’s data. Here, with our record-high bear population, a fairly recent study documented that black bears kill as many fawns as coyotes.
Finally, I read an article recently that mentioned that even fishers kill fawns when they find them. As most readers know, the Game Commission not all that long ago reintroduced fishers back into the Keystone State, and their numbers are growing steadily. Could that be bad news for the deer herd?
Winters in the Upper Peninsula of Michigan are significantly harsher than Pennsylvania -– it’s a different ecosystem -– so perhaps it’s apples and oranges. But does it make me a kook or a crank because I question these things?