GPS study confirms easy winter for deerGRAND FORKS — A pilot study of 10 deer fitted with GPS collars in a farmland-forest transition area of northwest Minnesota makes a strong case for how easy this winter has been on the animals.
By: Brad Dokken, The Dickinson Press
GRAND FORKS — A pilot study of 10 deer fitted with GPS collars in a farmland-forest transition area of northwest Minnesota makes a strong case for how easy this winter has been on the animals.
The Department of Natural Resources launched the study near Fourtown and Grygla, Minn., in January 2011, fitting 16 deer with the high-tech collars to learn more about the animals’ habitat preferences during different times of the year.
The study also aims to learn more about how the deer interact with livestock in the area, which isn’t far from the core area of a minor bovine tuberculosis outbreak near Skime, Minn.
The winter of 2011 was hard on the study deer, and wolves killed six of the 16 collared animals. According to Dr. Michelle Carstensen, Wildlife Health Program coordinator for the DNR, a seventh deer died of unknown causes and was scavenged by predators.
The DNR trapped and collared five new deer last March, and 10 deer now have the collars, which are programmed to fall off April 15, Carstensen said.
Last winter, almost all of the deer in the study made extensive movements, mostly to wintering areas with thicker cover. This year, the collared deer didn’t move much at all, and no mortality has been recorded.
“Last winter, half of them died,” Carstensen said. “Wolves hammered them. This year, they’re doing just fine, and only two of those moved.”
In one case, Carstensen said, a doe stayed in relatively open country until late February, when she hit the trail and moved 12 miles to Beltrami Island State Forest. Another doe near Thorhult, Minn., didn’t move for a day and a half after a late February storm and then made an eight-mile trek into the Red Lake Indian Reservation.
And one deer, Carstensen said, has stayed within a one-square-mile area since being fitted with the GPS collar in January 2011.
“Some deer are just obligated to migrate, and others are more on cue, whether it’s day length or snow depth or whatever it is that drives them,” Carstensen said. “There’s far less movement this year for sure.”
Dokken is a reporter for the Grand Forks Herald, which is owned by Forum Communications Co.