Hunters in Wisconsin reported killing four wolves in the first 24 hours of the state's wolf hunt. The Wisconsin Department of Natural Resources has set a statewide overall quota of 201 wolves. On Monday, two groups filed a 60-day notice of their intent to sue the U.S. Fish and Wildlife Service over the delisting of Great Lakes wolves.

Three days into the season, hunters in the northern wolf-hunting zones had taken over 60 wolves as of Monday, the Duluth News Tribune reports. Research biologist for the DNR, John Erb, tells the newspaper that about 1 percent of hunters have been successful. In western states in the past, hunting success have been less than 1 percent.

Minnesota hunters have killed at least 110 wolves in the first eight days of the state's highly controversial wolf hunt, according to the Minnesota Department of Natural Resources. The statewide quota for the early hunting season is 200 wolves, which runs through Nov. 18 or until hunters reach the limit.