The state of California is training dogs to sniff out quagga mussels (Dreissena rostriformis bugensis) on infested boats, according to this report from the Sacramento Bee. The dogs are far better than humans at locating the tiny bivalves, finding them faster and in nooks and crannies that would escape the human eye. It is a bit expensive to buy these persistent pooches - a single dog costs $8000 to $12,000. But with California already spending millions to deal with the recently arrives quaggas, that likely seems a small price to pay.
A quick perusal of the ISW archives brings up posts about dogs detecting Burmese pythons, mealybugs and spotted knapweed. Is there anything dogs can't
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