Moose: Unraveling a mystery

The dramatic decline of Minnesota’s moose population remains a mystery, though researchers are beginning to shed some light on the situation.

“Adult moose mortality should be about 10 percent, and it’s about 20 percent,’’ said researcher Ron Moen of the Natural Resources Research Institute at the University of Minnesota Duluth.

Though wolves are responsible for about 10 percent of the mortality, “almost 40 percent are just lying down and dying,’’ Moen told round-table participants on Saturday.

The radio-collared moose study also showed that 30 percent of adult moose were thin or very thin, indicating a health problem. The cow-to-calf ratio also has been declining, “and that doesn’t bode well for the population,’’ Moen said.

Calf mortality also remains a concern: Researchers documented a 70 percent mortality rate. Wolves were responsible for 68 percent of the deaths and black bears 16 percent.

While some people blame wolves for the demise of moose, Moen said the moose population would still be in peril in northern Minnesota even if there were no wolves.

Adding to the mystery: Small populations of moose are doing well in Voyageurs National Park and near Grand Portage and elsewhere in the U.S.