The Minnesota DNR is expanding its use of dogs to sniff out invasive zebra mussels.
The agency started with two dogs four years ago. This year they are adding two additional dogs.
The animals are trained to smell zebra mussels on boats.
"When they detect the odor of a zebra mussel they'll actually sit down to indicate that they've found that and then they get a reward," said K-9 unit coordinator Jason Beckmann.
The dogs' olfactory skills can find the invasive mussels in places human inspectors might miss.
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"Baby zebra mussels, what they call veligers, they can be present in water," explains Beckmann. "They can be up inside of motors, in bilges, live wells, things like that, that an inspector might not be able to see. And a dog can still smell that."
With four dogs on the prowl for mussels, the DNR is spreading the K-9 units across the state, with a handler and dog in the northwest, southwest, southeast and metro.
The new dogs are German Shorthair Pointers. Shelby is a female who will be based in the Twin Cities. Storm is a male who will patrol the northwest part of the state.
It cost $13,000 to buy and train the two new dogs, said Beckmann, with the cost being covered by a $25,000 federal grant.
The K-9 teams are also helpful in educating people about how to prevent the spread of invasive species.
"One of the really good aspects of the canine program is you can reach people of all ages. Everybody loves a dog," said Beckmann.
Sniffing out hitchhiking zebra mussels is a summer gig, but that doesn't mean the dogs are off duty the rest of the year.
"Our zebra mussel dogs are also cross trained to track people and find firearms and shell casings. Because in the off season we want to keep the dogs active and keep them busy," Beckmann said. "So they do a lot of stuff with our field officers during deer hunting season and fishing season."
Beckmann hopes each dog will be able to work eight years before retiring, and the agency plans to make K-9 conservation officers a permanent part of the DNR enforcement division workforce.