Nice to hear Florida Man has a voice. You, sir are a legend :)

Orcas rely on the salt in the water to keep their skin healthy. If they stay too long even fresh water they will succumb to infections. Other types of dolphins seems to be able to adjust a little better to shifting amounts of salt in the water. I have no clue about the larger whales but I suspect they have problems with fresh water because they wont float as easy in it.