Scientists warn of faulty Wisconsin wolf estimates

Scientists are warning federal wildlife officials that Wisconsin's Department of Natural Resources produced a flawed wolf population estimate for the 18 months after January 2012 when the animals were removed from a federal endangered species list.

The researchers, led by Adrian Treves, a UW-Madison environmental studies professor, said the DNR's 2012-13 wolf monitoring report omitted information on how many radio-collared wolves disappeared, didn't report the date of death of radio-collared animals that were recovered, or acknowledge the effects of poaching on the population.

The DNR under-reported wolf mortality at 28.22 percent, the researchers said in a letter sent to the U.S. Fish and Wildlife Service last month, estimating it could actually be within the 35 percent to 55 percent range for the 18 months through June 2013.

A DNR spokesman had no immediate comment. A spokesman for the USFWS' Midwest region didn't immediately return a message.

The federal government removed wolves in Minnesota, Michigan and Wisconsin from the endangered species list in January 2012. Days later, Republican lawmakers in Wisconsin introduced a bill setting up a four-and-a-half month wolf season. The legislation allows hunters to use up to six dogs to track and trail wolves. Animal rights advocates contend using dogs will lead to bloody hound-wolf clashes in the woods.

The scientists warned that hunting wolves with hounds is a new threat to the population and suggested additional regulation would be required to avoid unlawful or unsustainable killing.

The DNR examined 27 of the 35 wolves killed by hunters using dogs this past season and didn't find any evidence of fights or other illegal practices. The evaluation was inconclusive, however; the carcasses had already been skinned when the agency examined them.

The researchers also complained that the DNR included data from novice trackers in its 2013-14 monitoring report and barred the public from a May meeting in which data was aggregated and interpreted. The moves make it difficult to compare population estimates from year to year, they said.

The latest DNR estimates put Wisconsin's wolf population at somewhere between 660 to 689 animals, down from 809 to 824 animals in 2012-2013. The agency's board has set the kill limit at 150 wolves for the upcoming season, down from 251 last year.

The group recommended an independent scientific review of the DNR's data. They urged USFWS officials to consider placing the wolf back on the endangered species list before the wolf season opens in mid-October to allow time for the review and demand the DNR use a standardized format for its population estimates.