Fly over northeastern Minnesota with "Sky Dan" and you would see a moose. One time, he spotted 15 of them during an hour flight. The pilot was so confident that he even offered those on his aerial tours a money-back guarantee.
"If you didn't see a moose, you didn't pay," Dan Anderson, 49, said.
No longer. Mr. Anderson stopped providing refunds to customers in 2008. He was handing back too much money.
The state's iconic moose population has been mysteriously declining for years, a drop-off that pushed the Minnesota Department of Natural Resources this month to propose labeling moose a species of "special concern."
"It's a classification that means we need to pay attention to this species," said Richard Baker, endangered species coordinator for the department.
The exact reason for the decline remains unknown, though experts have named some likely culprits, including climate change, parasites, disease, predators and nutrition.
"It could be a host of things," said Lou Cornicelli, wildlife research manager for the Department of Natural Resources.
Mr. Cornicelli said moose aren't trotting off to other states or Canada, either.
"The ones in our state are just dying," he said.
For Minnesotans, those deaths hit home.
Moose are a cultural symbol of the wilderness and carry a certain mystique. The animal graces the signs of diners, bars, lodges and more.
Each fall, the city of Grand Marais holds its Moose Madness festival on a long weekend during moose mating season. "They do go a little crazy in the fall, which is a good thing if you keep your distance," said Sally Nankivell, executive director of the Cook County Visitors Bureau.
For three days, the town of roughly 1,350 along Lake Superior puts on a show. There are free stuffed toy moose for the children, stenciled moose tracks on the ground and a moose-themed poetry contest -- both haiku and limerick. The festival has its own mascot: Murray the Moose.
Though the Minnesota moose is in trouble, experts say it's premature to label the mammal a lost cause.
"It's not a worry they are going to disappear yet. It's more, 'Let's do what we can to get them back,' " said Ron Moen, a wildlife biologist with the University of Minnesota, Duluth.
From 2005 to 2012, the moose population in northeastern Minnesota dropped 48 percent to an estimated 4,230 animals, according to an annual aerial survey. In northwestern Minnesota, moose have largely vanished.
"We never definitively found out" what led to the northwest drop-off, Mr. Cornicelli said.
So Minnesota has launched an effort to stop the trend from repeating itself.
In January, a private company hired by the state will begin shooting tranquilizer darts from a helicopter at 100 moose, Mr. Cornicelli said. Once subdued, 75 cows and 25 bulls will be fitted with GPS-tracking collars.
Since 2007, the Department of Natural Resources and tribal staff have manned "mandatory moose check stations." Hunters are asked to collect blood samples, the whole liver, hair and an incisor tooth to determine age and then drop the samples off at the stations.
A special-concern designation would not stop hunting, which experts say isn't playing a role in the drop-off. That would change if moose are classified as "threatened" or "endangered" under Minnesota law.
Tour guide Jim Blauch remembers that about eight years ago it was not uncommon to see moose on drives from his lakeside resort to nearby Ely. Since then, though, he says he notices far fewer of them.
Families come to fish, canoe, explore the wilderness and simply relax at Moose Track Adventures -- the Farm Lake resort and guide service he owns with his wife, Joan. This year, he said, one group of visitors saw three moose out in the woods.
Mr. Blauch hasn't been so lucky. Despite his frequent trips into the woods as a guide, the last moose he recalls spotting was near the Canadian border about five years ago.
"It is kind of a bummer because when people think of northern Minnesota, they think of moose," he said. "Everything is moosey."science