Guess What Animal?

Here is a short riddle I wrote. Guess what animal I'm thinking of and comment.(Hint: None of the animals below are the one I am thinking of.)  ᵔᴥᵔ

What Animal?

A flick of the tail and a splash of the waves,

The ocean to them is no maze,

They jump up and down as if on a trampoline,

They have flippers and no wings,

Sometimes they can play with you or me,

Can you guess this creature that lives in the sea?