"Get outta here!"

Wiki:

Hoover (1971? – July 25, 1985) was a harbor seal who was able to imitate basic human speech.

Hoover was an orphan when he was found by George and Alice Swallow in Maine in 1971. George and Alice decided to take him home. At first the baby seal didn't want to eat, but soon he ate at the pace of a vacuum cleaner (hence his name). When Hoover outgrew the bathtub, he was transferred to the pond outside their house where he began to imitate people's voices. Again he was moved, this time to the New England Aquarium, where he told visitors to "Get outta here!" in a thick New England accent.

Thanks to this, he became famous, and appeared in publications like Reader's Digest and The New Yorker and television programs like Good Morning America.

Hoover died on July 25, 1985 due to complications during his annual molt. His obituary was published in The Boston Globe.

None of Hoover's six pups (daughters Joey, Amelia, and Trumpet and sons Lucifer, Cinder, and Spark) spoke, but his grandson Chacoda (or "Chucky") has shown an ability to be guided in his vocalizations. As of 2007, Chucky remains vocal but has not shown an ability to mimic human speech. Aquarium staff continue to work with him.