Opps, I swallowed a seal.

[Catherine]

A Humpbacked Whale was feeding on a school of fish when it started acting strangely. It accidently swallowed a seal with the fish. Humpbacked Whales don't eat seals so he had to spit it out. A whale watching tour was there to see the event.

https://www.theglobeandmail.com/world/ar...ack-whale/

It wasn't so nice for the whale. It would be like accidentally swallowing a fly. 
Think of what it was like for the seal. I doubt he expected to be spat out. 
The seal would be the stuff of legends, swallowed by a whale and living to tell about it.