REGIONAL—Are black bears in trouble in far northeastern Minnesota? After back-to-back poor food years and an exceptionally high harvest of female bears in management zones in the border …
REGIONAL—Are black bears in trouble in far northeastern Minnesota? After back-to-back poor food years and an exceptionally high harvest of female bears in management zones in the border country, wildlife managers believe it will take time, possibly a long time, for the bear population to bounce back.
It’s already taken longer than DNR wildlife managers had expected. The DNR slashed the number of bear permits it issued to hunters in northern Minnesota beginning in 2012 in an effort to rebuild a population that had fallen by 50 percent between 2000 and 2010. Twenty years ago, the DNR estimated the state’s bear population at 20,000-25,000, which prompted the agency to boost the bear harvest in order to reduce bear and human conflicts. The management decision worked, perhaps too well, notes Andy Tri, acting bear project leader for the Department of Natural Resources. “The bear population declined faster than anticipated, which is why we cut permits so dramatically in 2012 as an attempt to stabilize the population,” said Tri.
For the most part, the state’s bear population appears to be stable or increasing slightly, notes Tri, although that’s mostly because the population is increasing in the state’s no-quota zone, located on the south and west edges of black bear range. The bear estimate in the state’s quota zone, which includes northeastern Minnesota, dipped slightly last year, as another poor food year pushed the bear harvest over 3,000. In northeastern Minnesota, DNR studies indicate that hunter take comprises about 80 percent of black bear mortality in any given year.
Because the DNR’s population estimates reflect statewide data, they don’t provide much help in understanding what might be happening here in the North Country, where the potential for bear recovery is more limited. That’s true, in part, because the region’s limited food availability impacts bear reproduction. “The BWCA and areas of the Canadian Shield have the poorest foods in the entire state,” notes Tri.
According to Tri, relatively limited natural food in the far north delays the onset of sexual maturity among female bears, or sows, which typically don’t breed in the region for the first time until age five or six, about a year later than bears in more southerly parts of the state. Many, if not most, sows never live that long. The average age of a hunter-harvested sow is just three years of age, according to the DNR, which means a substantial amount of future reproductive potential is lost each year.
That fact reflects the somewhat limited tool kit available to wildlife managers when it comes to recovering the black bear populations. When the numbers of whitetail deer decline, for example, the DNR routinely restricts the harvest of female deer, or does, which are readily distinguished from adult male deer due to their lack of antlers. Maintaining more breeding does in the population allows game species, like deer, to recover more quickly from population declines, whether due to hunting pressure, predation, winter conditions, or disease.
While there are subtle differences in the appearance of female and male black bears, DNR wildlife managers have determined that limiting the harvest of females isn’t feasible, since most hunters won’t be able to reliably recognize the differences in the field. Which is why the DNR has not limited hunter harvest of black bears to boars only.
Whitetails also reach sexual maturity much sooner in Minnesota than do black bears, which gives whitetails much greater reproductive potential. Female deer in the state typically enter estrus in the November of their second year, or about 18 months after birth. In better habitat, they can even reach sexual maturity in the November of their first year.
In addition, whitetails typically breed every year, while black bears in the state usually breed once every two years.
The one factor that can help protect female bears is their greater reluctance to approach baits left out by hunters. That reluctance means that in an average or good food year, the harvest mix often runs 60-65 percent males, according to DNR data.
That protective factor disappears, however, in poor food years. Without alternative foods on the landscape, hunger drives female bears to hunters’ baits and the result is hunters taking more females.
“My quick summary of the Tower area shows 50.6 percent females in the harvest as of Sept. 14,” said Tower DNR wildlife manager Tom Rusch. “This is clearly very high. A bear harvest with such a high adult female percentage could have long term impacts on the bear population.”
Tri agrees. “When harvest is high during a bad food year, it can have significant implications on the proportion of the population that is made up of reproductive females,” he said. “We won’t know what the full effects of the season will be until we get the final age data back in February, but it’s been a hard couple years for bears in the Northeast.”
Bear recovery limited
Rusch predicts a decline in the region’s bear population this year and he expects the DNR will need to reduce its bear permit numbers in the future in order to help the population recover. Tri said it’s still too early to know for sure, although he acknowledges that the high harvests in 2020 and 2021 are “exceptional.”
The impact of lower permit numbers isn’t always predictable. DNR wildlife officials had hoped that slashing the number of permits issued to bear hunters, beginning in 2012, would allow the bear population to recover, but the population in the quota zone hasn’t shown much growth despite several years of historically low bear permits. That’s true, in part, because the decline in the number of permits has coincided with a dramatic increase in hunter success in recent years, at least in the part of the state subject to harvest quotas, which includes the North Country. As recently as the early 2010s, only about one-in-four bear hunters was successful. In recent years, however, 45-50 percent of hunters have bagged a bear, a remarkable change that has blunted the impact of permit reductions. Last year, 57 percent of hunters in the quota zone bagged a bear, which pushed the total harvest up to 3,203 bears, the highest since 2006. Tri estimates a final harvest this year of 2,900 bears, which (except for last year) would be the highest since 2007.
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