"Our goal is to significantly reduce the (deer) population in the area. We hope to get as many as we can," Manwell told Reuters in a telephone interview.

The agency is working on a plan to address the issue of deer on state-owned lands as well.

The operation will focus on an area west of the capital city of Madison in which a total of 14 deer have tested positive for chronic wasting disease (CWD). The illness, a fatal brain disorder affecting deer and elk, causes weight loss and other symptoms similar to mad cow disease.

While mad cow has never been diagnosed in the U.S. cattle herd, CWD has been present in North American deer and elk for decades, with most cases concentrated in Colorado, Wyoming and Nebraska.

There is no evidence that the disease can spread to cattle or humans.

In March, state officials announced that three Wisconsin deer shot by hunters last fall had tested positive for the disease, the first cases east of the Mississippi River.

The state Department of Natural Resources then killed 516 deer from the surrounding area and had brain tissue samples tested to gauge the scope of the outbreak. The agency said this week that the testing was complete, and that 11 deer from the sample group had tested positive for CWD.

Rather than wait for regular hunting season to begin in the fall, Manwell said the state wants to take quick action to stem the spread of CWD.

With a statewide herd of about 1.5 million deer, Wisconsin has more than Minnesota, its larger neighbor, and far more than states like Nebraska and Colorado, where CWD was first seen.

The Wisconsin deer population is also relatively dense, a factor that researchers believe could hasten the spread of the disease. No one knows exactly how CWD is transmitted, but animal-to-animal contact is a prevailing theory.

Wildlife officials want to limit such contact by thinning out the herd as soon as possible - even during the spring season when deer are rearing fawns and hunting is normally forbidden.

"We feel that this is an extraordinary situation, and it's going to take some extraordinary actions which may be distasteful," Manwell said.

Wisconsin is also considering extending the dates of its regular fall hunting season and relaxing limits on the number and age of deer that can be killed, Manwell said. Most permits allow hunters to take only one or two deer.

The Milwaukee Journal-Sentinel reported that the state wants to test 10,000 to 15,000 deer tested for CWD this fall.

Manwell said it was too early to project how many deer would be taken this spring. Some will be tested for CWD, while most of the carcasses will be buried in landfills.