2009 Moose Survey Results

VOYAGEURS NATIONAL PARK COMPLETES 2009 MOOSE SURVEY

Forty five moose were sighted during an aerial moose survey completed in January in Voyageurs National Park. Only 3 calves were seen and some bulls had not dropped their antlers yet. This survey, funded by the National Park Service, is the first complete survey of the park since 1992, when the park was estimated to have 35-72 moose. Personnel from the University of Minnesota Duluth, the U.S. Forest Service, and the Minnesota Department of Natural Resources assisted with the aerial survey.

It is difficult to see moose in late winter as they often remain under dense conifer cover, particularly in the cold and windy conditions encountered during the survey. As a result, less than 50 percent of moose actually present are seen during aerial surveys. Steve Windels, Terrestrial Ecologist with Voyageurs National Park, conservatively estimates that at least 80 moose currently live within the park.

“We are pleasantly surprised with the total number of moose we observed,” said Windels. “Based on moose population declines in the region many of us were prepared for the worst. We would have liked to have seen more calf/cow pairs, but they may have been in cover during the survey. We also saw more bulls than cows, possibly for the same reason.”

Voyageurs National Park is concerned about the long-term viability of its moose population given recent declines in moose populations in other parts of Minnesota and adjacent Ontario. Among factors possibly causing these declines are chronic stress related to warmer summer and winter temperatures and lethal effects of parasites transmitted by white-tailed deer such as brainworm and liver flukes.

The recent survey kicks offs a multifaceted project funded by the National Park Service and the U.S. Geological Survey that will provide Voyageurs National Park with information about these potential threats to the persistence of moose in the park. Voyageurs National Park staff, in collaboration with UMD’s Natural Resources Research Institute (NRRI) and the U.S. Geological Survey, will deploy radiocollars on moose in 2010.

“Moose seek cooler temperatures on hot summer days. We will use GPS radiocollars to measure movement, activity, and habitat use by moose in Voyageurs National Park next year,” said Ron Moen, Biologist at NRRI. “We will be able to identify forest types that moose use as thermal cover when it is too hot for them to feed.”

Two hundred fifty white-tailed deer were also observed during the survey. Deer numbers have generally increased in northern Minnesota in the last 20 years and the study will also assess changes in the relative number and distribution of deer within the park over that time. It will also examine the prevalence of brainworm and liver flukes in deer within the park. These parasites can be fatal to moose but rarely affect deer.

For more information, please contact:

Steve Windels, Terrestrial Ecologist, Voyageurs National Park, [phone], e-mail us