Recently, while watching Harbor Seals in Alaska, I got to talking to one of the clients, a studious biologist named Chris. He asked me if I had ever heard about a talking Harbor Seal that had been featured on NPR. My eyes widened in disbelief. Chris was a little fuzzy on the details, but as promised, he looked into it once he got home and forwarded me the details. Sure enough, seals can sometimes talk. The celebrity in question was named Hoover, the talking Seal. According to the New England Aquarium website, Hoover was found in Cundy Harbor, Maine in May 1971. Since he was believed to be an orphaned pup, he was cared for by his rescuers, George and Alice Swallow. When he outgrew his bathtub, he was moved to a nearby pond. It was there that the most bizarre thing happened. Hoover began to imitate human voices. He was soon transferred to the New England Aquarium, where he lived until 1985. He became quite a local celebrity, and was the focus of research into voice acquisition and mimicry in seals. Here are some examples of Hoover's talents. His voice was apparently quite close to that of Mr. Swallow.
It turns out that the legacy of Hoover lives on somewhat. His grandson, Chacoda, who currently lives at the New England Aquarium, shares some of the skills of his famous grandfather. Chuck, as he's called by his keepers, is being trained to mimic humans, in part using the recordings of his legendary grandpa. So far he can say "hi" and "how are you?". See here for more info, including a recording of Chacoda working on "How are you?" with a trainer.
For more information on Hoover, check out the New England Aquarium tribute page here. The photo of Hoover above first appeared in the Boston Globe.