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DNR dog sniffs out AIS mussels

DNR Water Resource Officer Larry hanson with his AIS-sniffing dog, Digger. They'll be in DL Saturday. Submitted Photo

In order to get a black lab interested in finding zebra mussels, start with venison.

“It’s easy to teach ‘the game’ of sniffing it out, because dogs love venison,” said Larry Hanson, one of three Minnesota DNR officers with dogs trained to sniff out zebra mussels.

He’ll be outside the Pavilion in Detroit Lakes Saturday at 11:15 a.m. to give a brief demonstration at the invitation of the Lake Detroiters Association, which holds its annual meeting that day.

Hanson said his dog, Digger, spent four or five weeks training with venison. “You put it in a box, or in a boat, or in a car or inside a building,” he said. “You teach them the process, and once they get the ‘game’ of finding venison, you can basically just imprint the scent of items you want them to search for.”

After the initial training, it took Digger, a shelter dog who is crazy about playing fetch with balls, about half an hour to learn how to search for zebra mussels, he said.

The most difficult thing was to find live zebra mussels after a long winter and cold spring.

“Zebra mussels had a bad year, too,” he said. “We found a lot of shells, but no live zebra mussels … we even went to Lake Minnetonka (with a dive team) and couldn’t find any.”

The problem was solved by the St. Paul Waterworks department, which had four semi-truck loads of live zebra mussels that its workers had cleaned out of pipes and water systems.

“They gave us some live ones to train with,” Hanson said.

The dogs can sniff out not just grown zebra mussels, but also groups of tiny veligers.

“You can’t see the veligers with the naked eye, that’s why you need to drain the water from the boat, live well and so on — otherwise you can take it to another lake and infest that lake as well,” said Hanson.

In California, where the use of zebra-sniffing dogs was pioneered, the dogs have found veligers as well as grown mussels, he said.

The three Minnesota DNR K9 water resource officers work both on their own initiative and at the direction of the agency. One lives near Rochester, one in Anoka, and Hanson spends a fair amount of time in the Alexandria area.

The dogs check boats coming out of infested lakes and check those going into lakes free of zebra mussels.

“If a dog hits on zebra mussels, that person will have to decontaminate the boat or trailer they’re found on,” he said. “It’s the officer’s discretion whether to give a civil ticket or a criminal ticket.”

A civil citation doesn’t go on a person’s record, and it’s a different process to fight it in court, Hanson said.

The DNR officer and his dog aren’t always a welcome sight to boaters.

“Up in Douglas County several weeks ago at an access, a guy with loud pipes on his vehicle saw me, gunned it and took off down the road,” he said. It turned out the man had no life jacket and hadn’t pulled the drain plug on his boat.

He got a $100 civil ticket for the boat plug violation. A criminal misdemeanor ticket would have cost about $140, Hanson said.

The three DNR K9 officers work on finding zebra mussels in addition to their regular duties, which includes wetland conservation — an ongoing battle, Hanson said.

(There are six additional water resource officers in the Minnesota DNR.)

The water resource officers, including the new K9 officers, become regular conservation officers during hunting season.

That’s why their dogs are also trained to find guns and ammunition.

“I could have used one of these guys last fall,” Hanson said. “I had a second-degree assault with a deadly weapon (case.)”

The dispute was between a man in a tree stand on his own property and several men from a neighboring property who went over to talk to him.

“He said, ‘You’ve got three seconds to get off my property or I’ll shoot you,’” Hanson said. “Rounds were hitting the ground around them as they ran.”

Hanson said his dog could have sniffed out the gun and ammunition used in the case. Hunting rifles can be expensive and are often hidden to avoid confiscation when hunters break the law, he said.

The dogs aren’t regular K9 dogs, they aren’t bite trained or trained to sniff out illegal drugs. But they will likely be trained to track down hidden objects.

California has 14 or 15 dog teams trained to detect zebra mussels, but Hanson isn’t sure how many teams the Minnesota DNR will train.

“We’ll see how things go with these dogs,” he said.

On a related note,  the Lake Detroiters will host flowering rush expert John Madsen as their keynote speaker.

“Lake Detroiters is pleased to have Dr. Madsen from Mississippi State University present at our Annual Meeting,” the group said in a news release.

“The ongoing flowering rush research project is making it possible to effectively manage this invasive and make our community lake a key asset for tourists and residents.

“The Pelican River Watershed has championed this effort along with the City of Detroit Lakes, Concordia College and the Minnesota Department of Natural Resources.  We have come a long way and are very fortunate to have such important research initiated right here.”