Amy Knowlton pilots the 29-foot research vessel Nereid out of Lubec harbor and into the waters of the Bay of Fundy, off of easternmost Maine. A scientist with the New England Aquarium's Anderson Cabot Center for Ocean Life Knowlton points to harbor porpoises chasing fish in the wind-swept waters on a recent morning.
Then something much larger appears off the stern.
"Whale behind us," Knowlton says, steering closer. "It's probably a humpback or fin whale, we'll get a better look."