First of all you can tame them using muttons now(also 50 a stack)

They are the kings in the sea. Nothing I repeat nothing come close to their sheer might and usefulness. Great health and great damage are given but more importantly they are immune to stun AND are the most agile and manoeuvrable among the heavy hitters of the sea.

There is no reason to tame any other sea creatures for battle once you get them.