Collared Moose Abandon Calves So Teams Get Stealthy
Researchers almost abandoned their study of Minnesota’s declining moose population when they realized that the mothers were abandoning their calves after being tagged. But reducing the number of people doing the tagging, along with getting the job done more quickly, may save both the calves and the project.
In the first study to use GPS to track newborn calves for a year, researchers used helicopters last year to get to newborns to weigh them, take blood samples and temperature, and collar them. But in the first year, nine of the 49 calves were abandoned by their mothers.
“It was all done in a matter of minutes and we were out of there,” Glen DelGiudice, a researcher for the Minnesota Department of Natural Resources, told Forum News Service.
The region in northeast Minnesota is piquing the interest of moose researchers because the population has dropped from about 8,800 moose in 2006 to about 4,300 this year.
The researchers hypothesized that the helicopter was the culprit, so they started going in on foot. But when seven newborn calves were abandoned this spring, DelGiudice thought he’d have to end the project.
“I was going to pull the plug,” he said. “That would have been the end of our calf research project.”
Unless one last idea worked: He reduced the teams of researchers from four to two, and reduced the amount of time spent with the newborns from a few minutes to under one minute. It’s not enough time to collect data, but it’s enough to get the collars on.
“We think we can do this very successfully with very minimal abandonment,” he told Minnesota Public Radio, “if we keep the handling team to an absolute minimum, and get in there and out of there very quickly. And it’s just worked really well.
The first 10 calves collared since then, between May 21 and June 2, have not been abandoned.
Why hasn’t this been an issue in other moose studies? The researchers suspect it has been, but without real-time GPS, other scientists may not have realized it was happening.
Photo: Glenn DelGiudice/Minnesota Department of Natural Resources