And this Idea again. At first it won´t happen it was discussed a thousands of times and always turned down.
Here are the reasons why, first there is the gameplay reason. With a bottle and an bucket full of water you have an unlimited and free foodsource.
Second is the Rp reason. Maiar are supposed to be rped in the water, so if they are to long on land they dry out and can´t breathe anymore.