I-Spy...........Smells

My father used to talk about Bloaters and, until now, I've never wondered what they were - and I've no idea whether he ever ate them! They sound disgusting - and a pair of bloaters sound rather rude.
According to wikipedia :- Bloaters, bucklings, and kippers
All three are types of smoked herring. Bloaters are cold-smoked whole; bucklings are hot-smoked whole; kippers are split, gutted and then cold-smoked.

So kippers are the only ones that are gutted before smoking.
That's another thing I've learnt today.