Summers have been getting hotter, and winters warmer, and not all wildlife can tolerate those temperature changes. At Voyageurs National Park in Minnesota, for instance, the warming climate is thought to be connected with chronic stress exhibited in moose in the park.
To get a better idea of how the climate is affecting the moose, and even wolves in the national park, staff will be capturing as many as six moose this month to fit them with state-of-the-art Global Positioning System collars. The project is part of a long-term investigaton into the potential effects of climate change and other factors on the long-term viability of moose in the park. It is a collaborative effort among scientists from Voyageurs National Park and the University of Minnesota-Duluth’s Natural Resources Research Institute.
Voyageurs officials are concerned about the long-term viability of its moose population, which currently numbers about 50 animals, 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.
This month's capture effort includes the recapture of six moose collared in Voyageurs in 2011 and 2012. The collars from the recaptured moose will be removed to download remaining data on the collars. The moose will then be fitted with new collars that will last for up to five years. These new collars will enable biologists to see what habitat the moose are using in the park, and where the cows calve, for instance.
Also in the works is a website that will allow the public to track the animals' movements as well. "It's a great opportunity for an interpretive tool," said Voyageurs biologist Steve Windels.
Voyageurs staff also plan to capture two adult gray wolves to attach GPS collars similar to those used for moose. The collaring effort, part of a larger wolf monitoring program in the park that includes snow tracking and other survey methods, will aid park managers in assessing the current status of wolves in the park. The last detailed population estimate of wolves in the Voyageurs National Park area was completed in 2001.
All animals will be captured by an immobilization drug administered via a dart gun shot from a single helicopter. The immobilization, which is temporary, allows handlers to safely attach collars and collect data related to animal health.
Blood and fecal samples will also be collected from each animal as part of a collaborative monitoring effort with the Minnesota Department of Natural Resources. The capture operation will be conducted by a private company, Quicksilver Air Inc., which specializes in the capture of wild animals from helicopters. Wildlife veterinarians from the Minnesota Zoo will also be on-site.
Some snowmobile trails may be temporarily closed inside Voyageurs National Park to allow for safe capture operations while the helicopter is in the immediate vicinity of a snowmobile trail. Closed trails will be adequately marked or staffed by Park Service personnel to alert park visitors. Closed trails may include the Chain of Lakes Trail and the overland portages of the Ash River to Kettle Falls Trail.
The capture operation is expected to be completed in one to two days between the dates February 10-18, dependent on weather conditions. Updates regarding trail closures will be reported in the weekly winter trail conditions reports, which are available on the park's website.