A dog named Tucker with a mysterious past as a stray on the streets of Seattle has become an unexpected star in the realm of canine-assisted scientific research.

He is the world's only working dog, marine biologists say, able to find and track the scent of orca scat, or feces, in open ocean water — up to a mile away, in the smallest of specks.

None of the orca monitoring could happen without Tucker and his wet, black nose — or the new tricks that he taught the scientists.

(READ the story and watch "A Nose for Research" from NY Times)

Also, click to learn more about Conservation Canines at their website.