DNR studying results from many angles
By JOHN PEPIN – Journal Staff Writer, The Mining Journal
MARQUETTE – From hunter success rates, to wolf pack movements and behavior impacts, Michigan Department of Natural Resources biologists expect to learn a great deal from the state’s first managed wolf hunt that began Friday.
As of 4:45 p.m. Saturday, four wolves had been killed of the total quota of 43.
On Friday, three wolves were shot, including one that was killed in Unit A in Gogebic County, leaving 15 wolves remaining to be harvested there.
Two more wolves were shot Friday in Unit B – which includes parts of Gogebic, Ontonagon, Baraga and Houghton counties – leaving 17 wolves left in the quota there. One wolf was killed Saturday in Unit C, which has a quota of eight and covers parts of Mackinac and Luce counties.
The hunt will continue until Dec. 31 or until the quotas in each of the management units are reached.
DNR furbearer specialist Adam Bump said the hunt is not about managing the number of wolves, but reducing conflicts. Beyond trying to maintain viability and not having gray wolves relisted as threatened or endangered species, the DNR doesn’t have set population goals.
“Our approach is novel for management of wolves. There has never been a hunt that’s been this localized, this focused and that has its primary or sole purpose to be to help resolve conflicts,” Bump said. “So when we’re looking at it, we’re implementing kind of a new idea and we’re going to be learning about it as we implement it.”
Bump said the quota of 43 wolves was derived from a few factors.
“One was that we knew we wanted to at least try to depress local populations, local abundance of wolves, a little bit,” Bump said. “And No. 1, are we able to remove some wolves to help reduce conflicts? No. 2, is the act of hunting wolves going to change wolf behavior and also help reduce conflicts?”
Bump said there aren’t any historical publications offering a formula indicating conflicts will be reduced by a certain amount if local abundance is lessened by a certain amount.
The DNR consulted a wildlife monograph that evaluated more than 40 studies to try to determine how many wolf deaths caused by humans had to occur to cause a wolf population to start to decline.
“Those studies showed that you had to have basically 29 (percent) to 30 percent mortality of the population before you could detect that human caused mortality was impacting the population,” Bump said.
The DNR studied each of the three wolf management units and estimated non-hunting human-caused mortality to be about 15 percent, which included road kills and poaching.
“We decided to look at trying to get about a 35 percent mortality rate in each one of those units,” Bump said. “So that’s a little bit above the rate that is needed to be able to even detect that you’re having an impact on those local populations and so we decided that we would try to harvest about 20 percent of the population in each one of the small units for an overall human caused mortality of about 35 percent.”
The wolf abundance for each the units was calculated from DNR winter counts and population estimates and models. The DNR recently estimated there were 658 wolves in Michigan.
“The expectation there is that it would have a minimal, undetectable impact on the U.P.-wide population, but we’re going to affect those abundances in each one of those units by a small amount,” Bump said. “We’re trying to reduce the specific wolves, the specific packs that we know have caused problems and to try to change wolf behavior with that harvest.”
Hunting pressure would not be expected to shift wolf territories.
“They would actually maybe, possibly move out of an area, but they aren’t going to really be able to go any further because they would start getting into another pack’s territory, so it could shift local populations around within the unit,” DNR wildlife biologist Brian Roell said. “We could create voids there where maybe other wolves maybe would come into that area and maybe establish new territories in there.”
Low numbers of wolves are being hunted within each unit.
“Likely we’ll just have some shifts in territory sizes, or maybe nothing at all,” Roell said. “These are things that we would want to continue to look at as time goes on and what kind of effects did we have on these packs.”
The DNR is also studying whether killing alpha males could have a negative effect on packs.
“It’s really an unknown at this point,” DNR wildlife biologist Dean Beyer said. “That’s been put forth as a hypothesis that if you disrupt the pack somehow, the animals that remain will go from being good wolves to bad wolves.
“It’s certainly something that everyone is going to be watching for, but you have to keep in mind that wolves don’t live all that long naturally and so there’s always turnover in these wolf packs. So that’s not a totally unnatural thing to have occur.”
Beyer said some research by Dan McNulty in Yellowstone National Park suggests a contrary result.
“He actually found that the younger wolves were actually the better hunters than some of the older wolves,” Beyer said. “That would kind of play against that idea that younger wolves are going to turn to livestock rather than natural prey.”
The DNR will be studying whether the success rate of Michigan’s 1,200 wolf hunters will match the roughly 4 percent found in Minnesota and Wisconsin last year.
“It’s not uncommon with populations of wildlife that have not been harvested in the past to have higher success rates the first couple times,” Bump said. “Just because they’re not used to having that risk associated with people. So it’s possible that you could have success rates decline after you’ve had one year of hunting.”
The DNR is curious whether the second year Minnesota and Wisconsin success rate will change.
“You could also have the opposite trend because we have hunters who are inexperienced that have never hunted wolves now,” Bump said. “And as they gain knowledge in how to hunt wolves, they may become more successful. The success rates are one of those things that we just don’t have a good handle on.”
Bump said success rates for other big game species in Michigan typically range between 25 percent to 40 percent.