TOWER—Registrations of fisher pelts continued their downward trend here, while trappers reported taking slightly more pine marten during the nine-day season held in late December.
Trappers tallied a total of 337 pelts during the annual registration day held Dec. 29 at the Tower, Eveleth, and Hibbing offices of the Department of Natural Resources.
That includes a total of 202 marten, 66 otter, 34 bobcat, and 35 fisher.
The fisher numbers have been declining noticeably for years, and this year’s total harvest of just 35 animals was the lowest in 20 years.
“It’s alarming,” said DNR Tower Area Wildlife Manager Tom Rusch. While wildlife managers expect considerable variability in trapping results from year-to-year, Rusch said the trend with fisher has become increasingly clear.
Research by DNR biologist John Erb has documented that fisher are particularly dependent on nest cavities in large aspen, which have become increasingly scarce on state-managed lands, where aspen stands are being managed on shorter rotations than in the past. Marten are less dependent on large aspen, as research has shown they more often use cavities in white cedar or underground burrows to sleep or raise young.
DNR officials had hoped that marten and fisher populations would recover when the agency slashed the trapping season for those two predators from 16 days to just six days several years ago. The season has since been increased to nine days, although the bag limit for both species remains at just two.
If registrations are an indicator, marten may have been more responsive than fisher to the lower bag limit, perhaps a reflection of the greater denning capacity on the landscape for the smaller martens.
“We tried to adjust the season to get some bounce back,” said Rusch. He said the lack of response from fisher points to a limitation of habitat. “We just don’t have that 18-inch tree anymore, like we did when fisher were at their peak,” he said.
The DNR held a second registration day for both otter and bobcat on Tuesday, Jan. 26. Results were not available as of press time.