Minnesota Natural Resources Commissioner Sarah Strommen has stepped up her campaign to protect wild deer against the spread of chronic wasting disease (CWD) by once again halting the movement of captive deer among deer farms.

Her third emergency action against deer farms has the potential to last much longer than the previous two, and it arrived five days after she put the Minnesota Board of Animal Health on notice that the DNR won't hesitate to exercise its new authority over the industry. In Minnesota and elsewhere, scientists have traced the geographic spread of CWD to the commercial trade of infected, farmed deer.

Assistant DNR Commissioner Bob Meier told reporters Monday that the latest ban against the intra-state movement of farmed deer and the ban against imports from out of state could last as long as 15 months, up to a year longer than the previous two movement bans combined.

The action comes as the DNR investigates CWD's known spread in Minnesota and possible other exposures. Meier said pausing the trade of captive deer will allow time for investigators from Wisconsin, Minnesota and the U.S. Department of Agriculture to unravel the "spiderwebbing'' of CWD transmission set in motion by a Wisconsin farm. The operator shipped 387 farmed deer to farms in seven states, including five to three farms in Minnesota. DNR Fish and Wildlife Division Director Dave Olfelt said it's possible that more of the suspected animals landed in Minnesota via resales from farms in other states.

"It's going to take a while to get this work done,'' Meier said.

Tim Spreck, a lobbyist for the Minnesota Deer Farmers Association (MDFA), did not comment. Previously, the association has strongly objected to the bans, filing lawsuits in both cases.

"We are still processing the current order, and I have not had a chance to discuss its implications with the MDFA Board,'' Spreck said.

A phone call and e-mail made directly to the deer farmers association were not answered.

The concern about Minnesota deer farms was heightened earlier this year when researchers detected CWD on a Beltrami County deer farm, the furthest north in the state that the disease has ever been found. The Beltrami farm had purchased deer from an exposed farm in Winona County. Most alarming was evidence that dead, infected deer from the Beltrami farm were dumped illegally on nearby public land that has since been fenced off by taxpayers as a bio-hazard to wild deer. University of Minnesota researchers have found loads of CWD contagions there, on the ground.

"This disease poses a clear, immediate and serious threat to Minnesota's wild deer, and these actions reflect what's at stake," Strommen said Monday in a news release.

The Minnesota Legislature this year gave DNR shared authority over the state's 253 captive deer herds, encroaching on governance previously dominated by the Board of Animal Health. The board has been criticized by DNR and the state legislative auditor for being soft on the industry and Strommen expressed new disappointment Oct. 6, by writing to the board's executive director, Beth Thompson.

The letter said Thompson's agency never replied to a set of suggestions made by the DNR in July for "practical'' changes that could protect wild deer from CWD. Should CWD become persistent in the wild population, Strommen wrote, there could be a "dramatic reduction in deer hunting'' — a tradition that generates $93 million a year in state tax revenue and $1.3 billion in economic activity.

The commissioner concluded by saying the DNR will use its newly granted authority and its existing power "to adopt those rules necessary to protect Minnesota's wild white-tailed deer population from the continued risk of CWD infection transmitted by captive white-tailed deer.''

Michael Crusan, a spokesman for the Board of Animal Health, said the board has no comment on the movement order and will uphold any rule changes stemming from "concurrent authority.''

The movement ban takes place at a time when breeders of genetically modified, big-antlered bucks often sell their animals to other deer farmers who promote fenced-in hunts for trophy seekers.

State Rep. Rick Hansen, a DFLer from South St. Paul who chairs the House Environment and Natural Resources Finance and Policy Committee, said Monday that he applauds Strommen for taking action.

"This shows that co-management is a failure and the DNR is stepping up to protect the public resource,'' Hansen said. His committee has discussed ending deer farming in Minnesota by buying out all existing operators.

Correction: A story Tuesday on Page C7 about the spread of chronic wasting disease (CWD) incorrectly described a Winona County deer farm. State officials classify the farm's deer herd as "CWD-exposed.'' The herd has been under quarantine since October 2020, but tests have not detected the disease.