Wisconsin’s nine-day gun deer hunt opens Saturday under a cloud of uncertainty.

The discovery of chronic wasting disease in 40 wild whitetail deer in south-central Wisconsin, and in captive deer on two game farms, has inalterably changed a tradition that lies at the heart of the state’s culture and identity.

“This deer season will be unlike any other that we’ve had,” said Tom Hauge, chief deer ecologist with the state Department of Natural Resources.

“But even with that, in so many ways this season will be the same as all the previous ones. Parents will still be bringing new kids into the woods. There will still be deer camps where new stories are created and classic oldies but goodies are retold, and perhaps embellished.”

When Hauge considers the size of the task ahead — the testing of 50,000 whitetail deer statewide — there are times, he said, his blood runs cold. But there is a payoff.

“When it’s over, we’ll know exactly where CWD is and where it isn’t,” Hauge said. “In the meantime, let’s not put too much of a damper on this activity that we cherish. Let’s not destroy the very thing we love.”

As of Friday, gun deer license sales statewide were down 19 percent, the DNR reported, at a time when state officials and conservation organizations are pleading with hunters to get out and reduce the size of the herd.

That could change this week.

Traditionally, a third of all deer hunting licenses are sold in the seven days preceding opening day. The state typically sells about 685,000 licenses a year.

There are 1.6 million wild deer in Wisconsin — far too many for available habitat to support.

Such numbers also mean densities that could hasten the spread of the disease.

The DNR regularly projects the number of deer that hunters will harvest each year. The agency has a remarkable record of accuracy.

Hunters killed 298,266 deer during the traditional gun hunt in 2001 and another 58,107 during Zone T hunts. Down only marginally from long-term averages, it was a sharp drop from the all-time record gun harvest of 528,494 deer in 2000.

There will be no predictions this time around.

“This is a year where it makes little or no sense to even attempt one,” Hauge said. “I have a feeling that if our harvest is comparable to last year, we’ll probably feel good about it.”

What happened?

It was 1998 and George Meyer, then secretary of the DNR, was worried about the spread of chronic wasting disease in wild deer and elk herds out West.

The disease was present in captive herds in Colorado, Montana and other Western states. Game farms were a primary suspect in its transmission, and the movement of captive deer and elk across state lines was escalating, in part because of “canned hunts,” in which individuals pay thousands of dollars to shoot trophy-sized bucks on fenced preserves.

“It became quite apparent that this was a ticking time bomb around the country,” said Steve Miller, DNR administrator of lands. “Montana had already put a moratorium on the import of farm-raised deer and elk into the state.”

Meyer and Miller met that year with Ben Brancel, then secretary of the Department of Agriculture, Trade and Consumer Protection, the state agency with regulatory authority over animal diseases on both deer and elk farms. They sought a moratorium on the import of game farm animals similar to the one Montana had in place.

“We wanted to in fact stop (CWD) before it started here,” said Meyer, now a visiting professor at Lawrence University in Appleton.

Brancel and other DATCP officials chose instead to follow the recommendation of deer and elk farmers that a voluntary testing program be instituted.

“We just didn’t have a legal or scientific basis to do it,” said DATCP spokesperson Donna Gilson. “Also, there was a real worry that if they imposed a moratorium, it would have the opposite effect and drive the trade underground, where we would not be able to trace it.”

Under Meyer’s instruction, the DNR then began random testing of whitetails shot by hunters. “We were the first state to do that,” Meyer said. “We didn’t think we would find it.”

Three years later, they did.

Fear that the disease could infect and kill humans (there is no such evidence) was fueled by scientific uncertainty, wild rumors and media reports.

No one knows how the 40 deer that have been discovered with CWD became infected — all of them in a tight cluster around Mount Horeb in Dane County — although an intensive investigation is under way.

Three possible scenarios have been broadly discussed:

• Feed containing ground-up tissue from a diseased animal was sold in Wisconsin and placed on the land for consumption by wild deer. Such “protein enhanced” feed has been banned, however, and the window of opportunity for the disease to enter Wisconsin through this route was small.

• A hunter killed a disease-carrying animal out West, transported the carcass home to Wisconsin, butchered it and disposed of the remains in a back wood lot, where the disease-causing proteins entered the food chain of wild deer. It is not clear how this would happen.

• A diseased game farm animal came in contact with the wild herd, either by muzzling with a wild deer through a fence, by escaping through a broken fence or by being released. CWD has been discovered on two Wisconsin game farms, six game farms are under quarantine because of the movement of animals between farms, and deer have escaped from at least one of the quarantined farms.

“I’d be surprised if that’s where it ends with game farms,” Meyer said.

New rules are in place that for now have stopped the legal importation of deer or elk. Strict new testing and record-keeping requirements are in place.

Hauge said DATCP is working hard with the DNR to trace CWD-infected game farm animals, a difficult task. Only a few of the state’s 947 game farm owners have refused to cooperate, he said.

“It’s easy to get into the blame game. There are a lot of good families whose livelihood has been threatened,” Hauge said.

All hands on deck

The DNR, under secretary Darrell Bazzell, has treated the arrival of CWD as an all-hands-on-deck emergency. The agency initiated what is says is the most ambitious wild-animal disease survey ever attempted, with plans to take brain samples from 50,000 or more deer this year, all across the state. Testing at this level, according to mathematicians, will allow the agency to determine with 99 percent statistical certainty where the disease is present.

For the wildlife survey to work, hunters voluntarily must bring deer to CWD collection stations that are being set up all over the state.

During the Zone T gun hunt in October, CWD collection stations were opened, with free test results for hunters who volunteered their deer heads. DNR officials expected a large number of volunteered samples.

“What we saw was a different affair,” Hauge said. “Even though a collection site was a couple hundred yards down the road (from a registration station), hunters frequently passed them by, saying, ‘Oh, I’m not going to take the time.’”

Many of these hunters, especially in central and northern counties, said they simply weren’t concerned about CWD.

There’s nothing wrong with that, Hauge said, except that the DNR needs the results. The agency requires about 500 deer heads from every county, and only hunters can make it happen.

“If I could ask one favor of hunters,” Hauge said, “if they are lucky enough to get an adult deer, I would sure like them to stop by the collection sites, if for no other reason than to bolster the confidence of their fellow hunters. I can’t think of anything better they can do to preserve the tradition of deer hunting in Wisconsin.”

Fear of the unknown

Many are uncomfortable with the uncertainties that surround CWD. While there is no evidence that the disease can jump the species barrier and infect other types of animals, or people, scientists cannot say with certainty that it cannot happen.

“The thing that makes everyone uncomfortable is what happened in Great Britain,” said James Kazmierczak, epidemiologist and public health veterinarian with the state Division of Public Health.

In the United Kingdom, “downed cows” were ground up and added to cow feed, creating a cannibalistic situation that some scientists believe is behind the spread of transmissible spongiform encephalopathies (TSEs) like “mad cow disease” in cattle.

More than a quarter-million head of infected cattle entered the human food chain, with ground-up brain matter — where the disease-causing prion is located — used in food products. Millions of people were exposed. Of these, 130 became infected with new-variant Creutzfeldt-Jakob disease, the human TSE. Fears that the disease would expand exponentially in the human population have not played out.

Even under such hideous circumstances as these, Kazmierczak said, the risk to humans was small.

“With 130 people out of that kind of denominator, the risk is less than dying in a plane crash or being hit by lightning,” he said.

There is no evidence that CWD in deer will jump species in this manner. People have been eating deer and elk from CWD-infected herds in Colorado for nearly 30 years, and there has been no link to human illness.

“You can point to a lot of things that are reassuring,” Kazmierczak said. “For all we know, you could live on a steady diet of deer brains from the (CWD) infected area and never get ill.”

But state officials are not dismissing the concerns. The consistent position of officials in all state agencies, along with the Wisconsin Medical Society and the World Health Organization, is that while there is no evidence that CWD can harm humans, scientists cannot yet rule it out as a human health threat.

Some hunters will decide not to hunt deer, not to eat venison. Some will decide to keep hunting and to eat the meat.

“Our take has always been to lay everything out and let everyone decide for themselves,” said Kazmierczak. “The important thing is that you are making that decision based on reliable data, as opposed to what you hear at the neighborhood bar or from someone who has something to gain.”

Some, like longtime hunter Dennis Gitter of Neenah, will take a middle road. He already has one deer in the freezer, and probably will add two or three more. He hunts in Shawano County. His venison will stay in the freezer until late winter or early spring when the statewide CWD survey is complete.

“I hunt close to Marathon and Waupaca counties. If all three counties are free of the disease, then I am going to eat it,” Gitter said. “Our whole family eats venison. I just want to be positive before I feed it to my kids.”

Future testing

Everyone’s best hope is that CWD will only be found in the 400-square-mile eradication zone. Years of intensive hunting and testing there could possibly eliminate CWD from Wisconsin.

“I do not anticipate finding CWD everywhere in the state,” the DNR’s Hauge said. “We might find it in one or two other areas, possibly. If that is the case, we will certainly need supplemental testing in those areas to get a better idea. Even if don’t find it anywhere (outside the eradication zone) we will set up a schedule of continued surveillance.”

Those kinds of plans have not been formed yet, but likely would involve intensive testing every three to seven years, Hauge said.

Meyer has hunted in the eradication zone, and plans to return there after the traditional gun season. Gun hunting in the zone continues non-stop through January. The DNR estimates that 3 percent of the deer in the zone are infected.

Some hunters in the zone dispose of any deer they shoot. Others take them home to eat. That’s Meyer’s plan.

“I would not hesitate to eat a healthy looking deer from the eradication zone, personally,” Meyer said. “It’s an unbelievable shame to see these healthy looking animals put into front-end loaders, headed for incineration.”