The Wandering Moose

Submitted by Bruce Auchly, FWP Region 4 Information Officer

After all the slicing and dicing and studying of wildlife, along comes an animal or two that just won’t fit into a category, showing us we really don’t know it all.

In the last two years, a pair of cow moose radio collared on the Rocky Mountain Front as part of a 10-year population dynamics study has displayed a wanderlust that has confounded Nick DeCesare, research wildlife biologist with Montana Fish, Wildlife and Parks.

“We’ve seen local migrations, but nothing like these two,” DeCesare said.

One female moose took off the summer of 2015 from the Pine Butte Swamp west of Choteau and strolled to Fresno Reservoir northwest of Havre. That’s a straight line distance of about 110 miles, longer the way the moose walks.

By fall 2015, the five-year-old animal had returned to Pine Butte Swamp and has not left since.

This summer a different moose – age three – took off west from the Rocky Mountain Front. She crossed the Continental Divide, walked through the Bob Marshall Wilderness, and ended up on the Clark Fork River near Deer Lodge and Anaconda.

This fall, she headed back, crossing the Divide near Roger’s Pass, spending time in front yards around Fairfield, then heading north past Choteau and was last seen near Conrad.

AAA couldn’t have come up with a more scenic trip.

“Most moose don’t move around a lot,” DeCesare said. “In fact, many moose will spend the entire year in an area covering only a few square miles.”

Of the 105 moose radio collared in this study, these are the only two to range widely.

DeCesare’s study is looking at what drives moose populations in three areas of the state: the Cabinet Mountains, the Big Hole and the Rocky Mountain Front.

Lots of problems in the moose population have claimed lots of headlines recently.

“In other parts of the world, moose face challenges of predation, lack of nutrition, parasites and diseases and climate effects,” DeCesare said.

Although some local studies have taken place on Montana’s moose population – the Yaak Valley in the 1980s and the Ruby Range and Tobacco Root Mountains in the 1960s and 1970s – no comprehensive look at the state’s population has ever occurred.

Now four years into his study, DeCesare can say each of the three studied populations is different for different reasons.

The Cabinet population survival of adult females is good but getting the calves to one year of age, called recruitment, is lower. Predation may play a role. Overall the population is steady.

In the Big Hole cow survival is down, possibly from parasites and disease, but recruitment is good.

The Front has the best population growth of all, he said.

“The Front is one of the few places in the state with a growing population,” DeCesare said. “They have a really high productivity, survival of adult cows and recruitment.”

Maybe that’s it.

Maybe the neighborhood got too crowded for the two females and they started looked for new addresses, perhaps a fixer-upper.

“Just when you think you’ve seen it all,” DeCesare said.