Sea creature, meanwhile, nervously nibbling shark's tail (5,5)

'shark's tail' is the definition.
The answer and definition can be both animals as well as being singular nouns.
Maybe they are linked in a way I don't understand?

'sea creature meanwhile nervously nibbling' is the wordplay.
I cannot really understand how this works, but
'creature' could be 'whale' (I have seen 'Large animal' mean 'whale' so perhaps 'animal' could also mean 'whale') and 'whale' is located in the answer.
The remaining letters 'minke' is a valid word which might be clued in a way I don't see.
This explanation may well be incorrect...

Can you help me to learn more?