Minnesota trying to save its moose
Wildlife researchers from across North America are in Duluth today as part of a developing effort to see if Minnesota can save its moose.
Hit hard by parasites and heat, Minnesota's moose numbers are shrinking and moose experts fear the state may be destined to loose the big, beloved animal for good.
The moose summit offers a snapshot of the moose situation in Minnesota and worldwide. It also serves as the kickoff for a seven-month moose advisory committee to decide what research is necessary to understand moose issues and then develop a management plan for the Minnesota Department of Natural Resources to follow.
The committee is ordered to report back next summer on what should be done.
"We're going to figure this out. We're going to set a course that's proactive,'' said Laurie Martinson, deputy DNR director. "There's nothing that makes your heart beat faster [than seeing a moose], and we want to make sure we save that for future generations.''
But a rapidly warming climate may be too much for moose to overcome, said Rolf Peterson, a world-renowned moose expert from Michigan Technological University.
"I don't know that we can do it,'' Peterson said of preserving moose in Minnesota. "The changes we've set in motion in terms of climate change are already there, are already in motion.''
Markedly shorter winters, hotter summer days and more extreme climate and natural phenomenon are all combining against moose on the southern edge of their natural range, Peterson said. The animal was built to withstand deep snow and cold. But even days in the upper 70s take their toll.
"It will be a challenge to hang on to a species [so affected] by summertime heat,'' Peterson said. 'Things are just changing too fast for moose to hang on in all of their former range.''
Peterson said moose are hit hard by even moderately warmer days because of their black coat, back hair and inability to perspire. Moose can only lose heat by breathing faster, he noted. When moose are overheated they don't eat, and if they lose too much weight they may not survive winter. It's believed some moose even perish from heatstroke.
Warmer, less severe winters also have produced unprecedented deer populations in northern Minnesota. Deer carry a brain worm that is harmless to whitetails but is fatal to moose.
In areas of even modest deer densities -- about 10 deer per square mile, which includes much of Northeastern Minnesota now -- the parasite becomes prevalent and moose die out.
Warmer weather at key periods also increase a bug called winter ticks, causing heavy tick infestations that bother moose so much that they rub off their insulating hair, leaving them open to death by exposure.
Wildlife experts say efforts to help moose hang on could include reducing or eliminating moose hunting. This year, about 2,700 hunters applied for just 250 permits to hunt moose. Minnesota hunters shot 110 bulls. Ojibwe tribal hunters shot another 30 or so.
But shooting only a few bulls each year is not believed to affect the overall population, said Dave Schad, DNR fish and wildlife division director. Schad said it's not clear how much longer hunting seasons can be offered.
"At some point the population will be low enough where we can't sustain hunting seasons,'' he said.
Other efforts could include drastically reducing white-tailed deer numbers in some areas to allow moose to rebound, but it's not clear if that would be publicly accepted or even work.
Peterson said habitat, namely tree cover, can be modified to encourage moose, such as leaving plenty of evergreen trees for moose to escape summer heat and winter cold. But that's already being done, he noted.
Moose were common across the northern third of Minnesota before settlers arrived. Their numbers were decimated by intense logging, farming and over-hunting, and moose hunting seasons were closed in 1921.
Moose numbers slowly rebounded, peaking in the mid-1980's with more than 4,000 moose in northwestern Minnesota and up to 8,000 in Northeastern counties. The DNR resumed limited hunting season in 1871, and moose seemed to be doing well.
Starting in the 1990s, however, the northwestern herd crashed. Now, fewer than 100 moose remain. Climate experts found significantly more hot days in the region and the overall growing season, between frosts, is now 20 days longer than a half-century ago. While several problems contributed to the decline of northwestern Minnesota moose, a long-term study pointed to the warming climate as the overriding factor.
In recent years, the Northeastern herd also has started to decline, by about 6 percent annually. The herd remains strong at about 7,600 animals. But wildlife officials fear the same rapid decline could strike the Northeast as it did the Northwest.
Pregnancy rates remain unusually low in the Northeast, and the number of moose that die from natural causes in Minnesota remains unusually high compared to Canada and other areas where moose are common.
Moose also are declining rapidly in areas of Northwestern Ontario where deer are now common, Peterson said.