MADISON, Wis. (AP) — Hunters shot and killed at least four wolves in the opening 24 hours of Wisconsin's first organized wolf hunt, the state Department of Natural Resources said Tuesday.

The first reported killing — a male — took place at 7:15 a.m. Monday in Rusk County, according to the DNR website. Another hunter in Vilas County took a female at 8:30 a.m. A third hunter killed a female at 4:30 p.m. in Iron County and a fourth killed a male at 6:15 p.m. in Eau Claire County.

The hunt opened Monday morning but hunters aren't required to report kills for 24 hours. As of mid-afternoon Monday the DNR hadn't received any kill reports.

The hunt is scheduled to end Feb. 28, but it could close sooner; the DNR has set a statewide limit of 116 wolves with zone-specific limits. As of Tuesday morning, hunters could still kill 31 wolves in the far northwest, 19 in the far northeast, 17 in the mid-northwest, 22 in the central, 5 in the mid-northeast and 18 in the south.

The DNR has awarded 1,160 wolf licenses through a computerized lottery, although little more than half of the winners had purchased one by Monday morning.

Wildlife officials estimate as many as 850 wolves roam Wisconsin and 3,000 more live in Minnesota. Farmers have complained for years about wolf attacks on livestock.

Federal officials opened the door to hunting in both states when they removed Great Lakes wolves from the endangered species list earlier this year. Legislators in Wisconsin and Minnesota quickly passed laws establishing hunts, and hunt legislation is pending in Michigan.

The hunts are a flashpoint of contention. Animal welfare advocates insist wolf populations in both Minnesota and Wisconsin are too fragile to support hunting.

The Center for Biological Diversity and Howling for Wolves have asked the Minnesota Supreme Court to halt that state's hunt before it begins on Nov. 3.

On Monday the Humane Society of the United States and The Fund for Animals notified federal wildlife official they plan to sue to force Great Lakes wolves back on the endangered species list. The groups allege the states are mismanaging the species.

Georgia Parham, a spokeswoman for the U.S. Fish and Wildlife Service's Midwest region, said in a statement Tuesday the agency doesn't comment on pending legal action, but that the wolves appear to be thriving in the region.

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