Back in 2008, Tucker the black Lab was just another canine resident at SnoLine Kennels in Arlington, Wash. — until he caught the eye of Sam Wasser, director of the Center for Conservation Biology and the Conservation Canines at the University of Washington.

“Tucker was everything we were looking for in a dog,” says Katherine Ayres, lead author of a recent study on whales published in PLoS ONE, in which Tucker had a starring role. “He was a play-driven black Lab that loved to work with his handlers — and he hated water!”

This proved to be a favorable personality trait, since Ayres and her team needed Tucker to stay put on a boat while using his stellar nose to sniff out killer whale feces that they could then collect and test for stress hormones back in the laboratory.

How a Dog Detects Whale Scat

Before Wasser came up with the groundbreaking idea to use a dog as a scat detector, researchers had to follow closely behind whales to collect samples — not an ideal situation when you're tracking animals that are already endangered.

But with Tucker onboard, the scientists could stay as far away as 400 meters from the marine mammals, reducing any disturbance to the orca pods.

“He also minimizes any bias in the sampling, since we are not selecting which whales to follow,” Ayres says, “making our sampling more random and more representative of the whales that are present.”

The ultimate goal of Ayres' study was to test the levels of various stressors in killer whale populations. Her findings: Not having enough salmon to eat is a bigger deal for whales than having boatloads of whale watchers in their vicinity.

It’s an important discovery because conservationists have been trying to decipher what’s most important when it comes to helping the endangered species thrive. Based on Ayres' work, researchers have concluded that while boats are a key consideration when it comes to whale welfare, the impact of vessels can be minimized as long as fish levels are kept high in the area.

What's Next for Tucker the Whale Tracker

Although Ayres' study is now complete, Tucker’s science career is just getting started. He’ll continue to track orcas through the University of Washington’s Conservation Canines program — and he recently traveled to St. Lucia to track iguanas.

Not a bad gig for a pound puppy.