A black lab mix named Tucker sits in the bow of a motorboat. As the boat travels around the San Juan Islands, in Washington, researchers on board watch for Tucker's behavior to change. When he moves his mouth up and down, wags his tail and leans his body way over the side of the boat, the researchers know Tucker smells what they are looking for: orca scat, or poop.
Tucker is one of three dogs in the world trained to track the scent of orca scat. It's an important job, says Samuel Wasser. He is the director of the Center for Conservation Biology at the University of Washington. The center's group Conservation Canines trained Tucker.
Orcas, also known as killer whales, are not generally endangered. But the orcas that live in the waters near the San Juan Islands are endangered. Chemicals found in their scat can help researchers learn how to protect the whales. "Measuring what comes out is a useful way of understanding what pressures animals are under, so we know what to fix," says Wasser.
A Moving Target
Orca scat is not easy to find. It smells like salmon and is often the color of the water. Because Tucker works on a boat, he can't simply walk over to the scat to show where it is. He must signal the boat's pilot where to go while the scat is floating in water. "It's a moving target," says Wasser, "but Tucker still gets it."
Tucker knows that when he finds a sample, he'll get his ball as a reward. "The dogs we use love to play so much that they will do almost anything to get the ball," says Wasser.
At Conservation Canines, Tucker and other dogs put their love of play to good use. They take part in programs that help endangered species around the world. Wasser was the first to train and use dogs for this purpose.
By collecting frequent samples from the San Juan orcas, researchers have learned that the whales' biggest problem is a lack of fish to eat. "We couldn't do this without Tucker," says Wasser. And for that, Tucker deserves a special treat.
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