Minnesota moose: Can they be saved?

GREENWOOD LAKE, MINN. -- The young bull moose heaved himself out of the snow and lumbered away, paying no mind to the pod of humans who watched anxiously from a few yards off as he disappeared into the gloom of a winter day.

Moose Number 1160, foraging in the brush northeast of Two Harbors, had been tracked by helicopter and brought down by a sedative dart. When he woke up, a GPS collar adorned his thick neck and began sending more text messages than a teenager to researchers in Duluth, who will track his every move for the next two years.

If he lives that long.

Biologists are in a race to discover if they can save Minnesota's moose before they disappear from the state. Two years ago, researchers reported that the iconic North Woods animals appear to be succumbing to Minnesota's warming climate. Now, in a new round of studies, the scientists hope to discover whether humans can protect them from rapid ecological changes, including disease, parasites and heat stress. But if, as many fear, Minnesota is simply getting too warm, then within a few decades the moose will become just a symbol of a place that used to be.

"Do we just stop and let them disappear?" asked Ron Moen, a University of Minnesota Duluth biologist who will be following Moose 1160 and 62 others in a two-year study. "I would say no. Just about everyone who talks to me about moose says they want to keep them here."

But the political climate may turn out to influence their fate as much as global warming.

Funding promised for the next critical phase of moose research is at risk from two powerful Republican legislators who have said that they are skeptical of research or projects related to climate change. One project that could get curtailed is an ambitious $500,000 study designed to determine precisely why moose are dying with such startling speed.

Moose were once everywhere in the Minnesota forest. But the latest aerial survey by the Department of Natural Resources (DNR) shows their numbers have dropped from 8,000 in 2005 to fewer than 5,000 today. They are also in decline on Isle Royale and southern areas of Manitoba and Ontario.

In the northwest corner of Minnesota, they are gone.

A pattern emerges

One of the many puzzles is a phenomenon one researcher described as "tip-over disease." The term makes biologists cringe a bit now because it's so imprecise, but it aptly described what they saw: apparently healthy adult moose dropping dead in the middle of summer for no clear reason.

There's always a reason, of course. But identifying the cause of death in an 850-pound carcass that has been chewed by scavengers in the middle of the woods is not an easy task. Nonetheless, that's what Minnesota researchers started doing in 2002 with 116 radio-collared moose. By the time the study ended, six years later, 85 moose were dead -- 49 from unknown causes.

But when they compared the outcome to temperatures, the researchers found a deadly pattern. A majority of the unexplained deaths were linked to higher than normal January temperatures, said Mark Lenarz, the DNR biologist who led the study published in 2009.

Moose are superbly adapted to cold. At temperatures above 23 degrees Fahrenheit in winter and 57 degrees in summer, they burn energy to keep cool, according to one study from Canada. In summer, that means they stop their round-the-clock browsing and, like a hot black Labrador retriever, find a cool place in the shade and pant. If they don't eat, they don't put on enough fat to survive the winter. If they burn up their fat too fast in the cold months, they might survive the winter only to die in the spring.

And like their cousin the cow, Lenarz said, they might develop immune weaknesses when they get hot, making them more susceptible to disease and parasites they pick up from a deer population that has exploded into moose territory.

Zeroing in on a cause

Lenarz, who has studied moose in Alaska and Minnesota for decades, is among those who believe climate change means their fate is already determined. "I'd like to think I'm wrong," he said.

But there are enough conundrums to keep some biologists as stumped as they are hopeful. For instance, though moose have disappeared from northwestern Minnesota, they seem to be thriving in North Dakota, in agricultural areas and grasslands that have never been their natural habitat. Biologists are astonished at photos of moose browsing in sugar beets and sunflowers.

"It's hotter there, and there is less shade," said Erika Butler, a DNR wildlife veterinarian. "And they are dropping triplets on the prairie. There has to be something else going on."

That's what brought Butler to her knees next to Moose 1160 a few weeks ago. He had been brought down by a careful choreography of machinery. First, a small plane circled above the snowy landscape looking for the telltale dark backs of moose. Once the animals were sighted, the pilot called in a helicopter that swooped in under the low cloud cover. A sharpshooter hung out the door and took aim with an anesthesia gun -- one shot and the moose slowed and collapsed in a stretch of tall brush.

Notified by radio that the moose was down, Butler and others in the research group took off on snowmobiles across Greenwood Lake. They found the young bull peacefully asleep in the deep snow, his long legs curled beneath him.

He had one antler. The other, marked by a bloody stump, had already been shed. Butler opened an ultrasound machine and measured the fat on his rump. She took blood samples, collected scat, hair, a few of his winter ticks and gave him a dose of antibiotics. Another shot reversed the sedative, and half an hour after he'd been brought down, he was up and away.

Now, Moen and his colleagues will be able to intimately observe his every movement for the next two years, thanks to the remarkable technology hanging around his neck. The device on his collar will record his location every 20 minutes and the ambient temperature. An activity counter will record his movement every five minutes, telling researchers whether he is eating, sleeping or chewing his cud. Six times a day, all that data from 63 moose in the Arrowhead region, the Grand Portage Chippewa reservation, Quetico Provincial Park in Canada and Isle Royale, will be texted via satellite to the researchers' computers.

In two years, having transmitted a treasure trove of data, the collars will drop off.

All hands on deck

Moen said the data will help scientists understand the roles of diet, habitat and weather.

What it won't tell them is why the moose are dying.

That could come next winter, through a sort of moose CSI project headed by Butler, who hopes to collar 100 specimens. In addition to the other data, the devices would emit an all-hands-on-deck text alert if a moose stops moving for four hours -- a clear signal that it has died. A handful of wildlife teams around the state will be poised to go after the carcass before it's eaten by scavengers. They will conduct necropsies on the spot, or use snowmobiles and four-wheelers to haul all or parts of it out of the bush and into a lab. "Without it, we will never know why they are dying," Butler said.

More important, she said, the answers could ensure the moose's survival in Minnesota. If the threat is parasites from deer, the deer population could be reduced. If it's tick-borne diseases, then prescribed forest fires could help. If they are nutritionally deprived, their habitat could be improved.

This week Butler will have to defend her proposal before the new members of a legislative and citizens committee that controls her funding. Money for both her and Moen's research comes from the state's Environment and Natural Resources Trust Fund, which funnels about $25 million a year in lottery proceeds to environmental projects. Moen's was approved by lawmakers last year; Butler's is up this year.

Rep. Dennis McNamara, R- Hastings, the new head of the House environment committee and a new member of the trust fund panel, told the group last week that he's not interested in funding research. His Senate counterpart, Bill Ingebrigsten, R-Alexandria, told the group he thinks global warming is a "farce" and a "fallacy." They have already canceled 25 recommended projects. Butler's is one of about 16 others to be reviewed Monday night.

She'll get five minutes to make a case for the moose.

"If I can't convince them ... then we won't be saving the moose," she said.

Josephine Marcotty • 612-673-7394