This is the only sea mount you should currently use for adventuring or the underwater caves. High levels easily tear through alphas and other hard to kill creatures like squids or mosas without the fear of dismounting due to squids or eels or jellyfish.
Do not be almarmed by it taking damage in deep water, its very small and takes a long time to kill your whale and can easily be healed by surfacing. The underwater caves have pockets you can surface at to heal. The surface healing can out-heal almost all wild dino damage and a lot of the cave damage. Fight at the surface if you can.
They also generate oil over time. They can only carry 20 oil at a time though so make sure you empty it often. The oil also spoils so use it quickly.
You can also press left trigger at the surface to jump and spray water. Careful not to beach your whale in the process though.
A great beginner tame, once you have an icthyosaurus, you can swim up to it and passive tame it. I just tamed one, and less than 5 minutes after I tamed a level 4, it’s killed 2 megalodons and 4 mantas. Like so noobs and beach bobs can see.
Good fighter, immune to jellies, supernatural healing boost at the surface, produces oil in its inventory, impervious to squid grabs, looks kinda cute too, only one bad thing about it: it gets squashed in the deep! Only slowly but the damage is there!