The once-thriving moose population in northwestern Minnesota has all but disappeared, and the remaining population in the state's northeastern region is on pace to die out in as soon as 20 years, but no one knows why.

The state's Department of Natural Resources (DNR) is undertaking critical new steps to protect the moose and possibly solve the mystery of their decline. The estimated moose population of 4,200 is nearly half the size it was in 2006. Adult moose are dropping dead, and the survival rate for calves is poor.

Last month, the DNR proposed classifying the animal as a "species of special concern," the initial step toward endangerment status. It's an important change, though it wouldn't stop moose hunting. The DNR says the crisis doesn't warrant a hunting ban but could in the future. Its management plan calls for ban if the bull-to-cow rate drops below 67 bulls per 100 cows for three consecutive years.

Lawmakers are expected to debate the matter, too. Because of a strong, bipartisan hunting faction with members in key leadership positions, Minnesotans advocating more aggressive policy changes to protect the moose face an uphill battle.

During last year's 16-day hunting season, 46 bulls were killed by state-licensed hunters. The DNR says hunting isn't the problem -- because of harvest limits and because only males are targeted. Because bulls breed multiple females, the overall moose population can remain intact as long as that breeding is sufficient.

Some Minnesotans want to ban hunting to increase their chances of seeing a moose. Spotting them is getting more difficult by the day.

As part of a new effort to understand moose mortality, this month researchers will begin equipping 100 moose with GPS collars that track their movements. Twenty-seven of those moose will also be implanted with devices that will monitor their body temperature and heartbeat. The measures will hasten recovery of dead moose before they decompose, which is critical to identifying the causes of death.

The $1.2 million project is being funded from the state's Environmental and Natural Resources Trust Fund. The findings will supplement other data collected over the years and will provide a more thorough scientific picture of the situation.

Researchers suspect that the rapid decline of moose is related to a warming climate, to parasites carried by deer, to disease, or to a combination of those factors. Wolves prey on adult moose, but aren't considered a significant factor in their depletion. Their impact on calves is uncertain.

The state should continue to pursue reasonable options to save the iconic moose, which is so identified with this state's culture that it was lionized by the 1960s television cartoon character Bullwinkle J. Moose of the fictional Frostbite Falls, Minn. Sadly, even if the cause of the decline in the moose population is discovered, there's no guarantee it can be remedied. But we won't know unless the research moves forward.


An editorial of the Star Tribune, Minneapolis.