CHICAGO — It wasn’t long ago that thousands of moose roamed northwestern Minnesota, affirming the iconic status of the antlered, bony-kneed beast from the North Woods. In just two decades, though, their numbers have plummeted, from 4,000 to fewer than a hundred.
They didn’t move away. They just died.
The primary culprit in what is known as the moose mystery, scientists say, is climate change. It has systematically reduced the Midwest’s already dwindling moose population and provoked alarm in Minnesota, where wildlife specialists gathered for a “moose summit” last month in Duluth.
“There’s not a lot of opportunity to turn this around,” said Mark Lenarz, a wildlife research specialist at the Minnesota Department of Natural Resources.
Temperatures tell much of the story. Over the past 40 years in northwestern Minnesota, the average winter temperature has risen significantly — 12 degrees — while summers are 4 degrees warmer.
Solitary and temperamentally grumpy, moose have made it clear in their estimated 13,000 years in North America that they hate warm weather.
Concern about the fate of the moose comes as the Bush administration is revising endangered-species regulations in ways that prohibit federal agencies from evaluating the effects of increased global warming on endangered species.
Officially, the moose is not endangered in the United States. But it is in danger of disappearing from the Midwest. Roughly 7,700 moose reside in Minnesota, nearly all in the northeastern section of the state. That is a drop of almost 50 percent in the past 20 years.
Isle Royale National Park, a 45-mile-long island in western Lake Superior, has about 650 moose, down from 2,500 in 1995. Michigan’s sparsely populated Upper Peninsula has about 450, and that population has remained steady, according to a wildlife biologist at the Michigan Department of Natural Resources.
“The trends for the past 20 years are pretty clear, and if they keep up, there won’t be any moose in 50 years,” said John Vucetich, a population biologist at Michigan Technological University in Houghton.
One of the many questions raised by the demise of the moose is: What does it mean if the moose go away?
“That’s the $64,000 question,” Vucetich said. “As the climate warms, some creatures will do better, some worse. For moose it’s fairly straightforward that we’ll lose them . . . and there are a lot of people who identify with moose.”
That identity, from wooden carvings to giant polystyrene moose next to roadside restaurants, helps define the region’s image.
“They’re a symbol of the great north, of wilderness, and a lot of people would not want to see that go away,” Vucetich said.
When temperatures rise, the moose have to work harder to obtain food and find places to stay cool. Lenarz said that affects their immune systems, prevents them from putting on more fat in the summertime (which they need to get through the winter) and makes them vulnerable to infestations from parasites.
Heading north to cooler climes is not an option. “When moose are in trouble, they don’t move. They die,” said Rolf Peterson, a research professor at Michigan Tech and the chairman of the Minnesota Moose Advisory Committee.
