MINNEAPOLIS — Minnesota's midwinter wolf population has fallen by about 710 animals over the past five years to around 2,211, wildlife managers announced Tuesday, attributing the decline to fewer deer for wolves to prey upon and the resumption of sport hunting and trapping of wolves last fall.
Officials with the Department of Natural Resources stressed that wolves are resilient and the decline is no reason to fear for the species' survival in Minnesota. They pointed out that the new estimate remains well above the state's minimum goal of at least 1,600 wolves, and higher than the federal government's recovery goal range of 1,251 to 1,400. Researchers also estimate the state has 438 packs with an average litter size of six.
"We still have a robust wolf population here in Minnesota, and we can managed a regulated hunting and trapping season without having a long-term negative influence on the overall population," Dan Stark, the DNR's large carnivore specialist, told reporters on a conference call.
But Stark said the maximum harvest quota will likely be proportionately lower than last fall and winter, when hunters and trappers killed 413 wolves during the state's first wolf season since the animals came off the endangered list in the region. He said the DNR will likely announce the actual target and other details about the season later this month.
Wolf hunting opponents said they were surprised and dismayed by the size of the decline from the 2008 estimate of 2,921, and called on the DNR to cancel the upcoming season. They said they found the decline in the average pack size from 4.9 in 2008 to 4.3 this winter particularly alarming, saying the loss of breeding wolves reduces pups' chances of surviving because there are fewer adults in the packs to raise them.
"This is one big huge guessing game that is taking unnecessary risks with an animal that we spent tax dollars bringing back, and now we're going to spend tax dollars making sure we don't kill too many. It's totally nuts," said Maureen Hackett, founder of Howling for Wolves.
Howard Goldman, the state director for the Humane Society of the United States, said the decline "came out of the blue. Everything I've heard thus far and everything the department has published indicated the population was stable and perhaps increasing slightly."
"This survey shows there's no need to hunt Minnesota's wolves," said Collette Adkins Giese, an attorney with the Center for Biological Diversity. "The population is on the decline and Minnesota's wolves really are too important to the ecosystem to be killed off for sport."
The DNR conducts comprehensive wolf population surveys every five winters, when the animals are at the natural low point of their population cycle and the snow cover and lack of leaves on the trees makes it easier to count them. So the new estimate reflects deaths from the hunting and trapping season, natural mortality and the nearly 300 wolves killed for predator control last year, but not the 2,600 pups the DNR estimates were born this spring.
The survey also found that Minnesota's wolf range, which generally overlaps the state's forested regions, has stayed about the same over the past five years, expanding slightly in some areas along its southern and western boundaries.
DNR research biologist John Erb said the figure of 2,211 wolves is just the agency's best estimate, and the margin of error is roughly plus or minus 500, which means Minnesota's wolf population could be anywhere between 1,652 and 2,641. The agency's critics said the low end of that range is too close to the state's target minimum of 1,600.
Since deer are wolves' main source of food, the 25 percent decline in the deer population in the state's forested areas over the past five years was likely the greatest factor behind the lower wolf numbers, the DNR officials said. The agency deliberately took the deer population down in many areas as part of its long-term management plan, and now seeks to hold those populations steady or let them rise in some areas, said Paul Telander, the DNR's wildlife section chief.