Dogs' ability to find birds, rabbits, lost children and prison escapees is legend. Now their skills are taking on new dimensions as they hunt for invasive weeds in a bid to protect the land's biodiversity.
Kim Goodwin, a graduate student and staffer in the Invasive Weed Prevention Program housed at Montana State University, is on the leading edge of finding out just how finely attuned a dog's snout can get. Her project is in Beaverhead County with Alice Whitelaw of the Working Dogs for Conservation Foundation.
Previously, Goodwin's master's degree work helped document dogs' ability to find early invasions of spotted knapweed better than humans. Now she is working to better understand the ability of dogs to detect isolated dyer's woad plants.
To the outsider, the work looks like it is fun for Camas, a 9-year-old German shepherd. She sniffs through the training field near Lima. When she finds a dyer's woad plant, she takes a little prance into the air and then pounces her snout right into the middle of the plant. Her rewards are swift and sweet: high praise from Whitelaw and a good toss of Camas' favorite ball.
A pattern sets in that Camas anticipates. Walk with Whitelaw, sniff, sniff, find, prance, pounce. Goooood dog. Fetch the ball.
Give her lots of the above and you have one happy dog. Find dyers woad that would otherwise be missed, and you have one happy county weed control department.
Dyer's woad is native to southeastern Russia and was first reported in Montana in the 1934. It displaces native plants in healthy ecosystems that are valuable for livestock and wildlife.
"Beaverhead County has had a formal eradication program for the last 20 years," Goodwin said. "But even if one plant is missed, that plant seeds and reinvades the site. For eradication to work, we need to find every plant."
That's where the weed-sniffing dogs come in.
Amber Burch, assistant weed coordinator for Beaverhead County, said that the benefit of the dogs is that they can get into the taller sagebrush and willows where humans can't see well. The drawback, however, is that training requires that some weeds not be pulled or sprayed when first found. The training, in effect, requires "just-in-time" weed management at training sites.
"Amber and Monica Pokorny, who has been overseeing the dyers woad project, have allowed us to manage about a quarter mile stretch on the railroad tracks and into the willows," Whitelaw says. "We're making sure we pull off new blooms and new growth, or we pull the entire plant. So we have to not only train the dogs but also manage the site and report that to Monica."
Human weed control efforts can only be partially effective. There will be small weeds unseen or moderately sized weeds hidden by shrubs. In field trials in 2006, three dogs averaged finding 92 percent of the knapweed, while humans found 76 percent. Using multiple dogs as a team, however, the dogs success rose to 100 percent.
The idea in Beaverhead County is to follow human detectors with trained dogs to achieve near-100 percent control.
But weed-sniffing in the wild is complicated. By comparison, drug-sniffing dogs have it easy, Whitelaw said. They go into a room dominated by the smell of humans, plastic, metal and leather, and sniff for something refined from a plant. A weed dog goes into a field with, perhaps, 20 types of plants. The "vapor constituents" of weeds and plants can be very similar but in different ratios, and that is what the dogs are being trained to detect -- just the right ratio.
"The dogs are trained to associate whatever scent you are training them to a highly prized reward," Whitelaw says. "The dog lets you know what that is. The dog has to be obsessed with a hunt drive and a play drive. It finds the target because it knows the minute it targets that scent it gets the reward. If the dog likes to tug, you play tug. If it likes to retrieve, you retrieve. Then the dog goes back to work."
Camas has been working since she was two years old and now has 10 scents she can target, including black bear, grizzly bear, mountain lion, wolf, swift fox, kit fox and desert tortoise.
The handler needs to be trained as well as the dog, Whitelaw says. Long before the dog works in a rangeland setting, it is trained on weeds in a controlled setting. The dog learns how to work on weeds, and a handler learns about the dog and how to recognize when it is tired or has other needs. The program at MSU has facilitated the training of four dogs on weeds, and there are also a few young dogs in training.
Goodwin will take information learned in Beaverhead County and use it to integrate dogs as new members of weed control teams.
"We're hoping to eventually be able to deploy canines and handlers to help county weed districts with eradication," she said. The project is supported by the Montana Department of Agriculture and MSU.
It's a challenging goal: protecting the land for native plants by using dogs to sniff out the opposition, but the bottom line is pretty promising: Dogs love to sniff, and they are really, really good at it.