waterbreathing leaves you when you are in the croc form, quite annoying when revert and you die to it under water. You get no warning, ei (blue face) you just die. Tested to see if waterbreathing leaves you just by shifting normally with any other form, and it does not.

When you shift into a water form the water breathing spell is stripped because the form has it naturally. When you revert you aren't affected by any water breathing.