By: News Tribune staff, Duluth News Tribune
Minnesota and Wisconsin estimate their wolf populations during mid-winter, when the populations are typically at their lowest. Here’s what happens through the year after that, using Minnesota’s estimated 3,000 wolves as an example.
“If our estimate is 500 packs, and we believe almost all wolf packs will have pups, that could add as many as 2,500 pups on the ground, or an average of five per pack,” said John Erb, furbearer research biologist with the Minnesota Department of Natural Resources. “That’s not far from a doubling of the population.”
That population then will start dwindling through the year as mortality sets in or animals disperse, Erb said.
“Perhaps 50 percent of the pups, on average, don’t make it to the fall,” he said. “Some years it may be 85 percent. Some years perhaps it’s 20 percent. It’s a difficult variable to monitor, but clearly in a stable population, many do not survive their first year.”
In addition, there’s adult wolf mortality. Some wolves are now taken by hunters and trappers. Some are taken as the result of livestock depredation. Some die from the effects of mange. Some are hit by cars. Some die in fights with other wolves.
Minnesota’s wolf population has remained relatively stable over the past 10 years, Erb said, though short-term or localized fluctuations certainly occur as with any wildlife population.