Can dolphins or whales live in fresh water?
They don’t need to breathe in water so assuming they have enough prey I don’t see why the water’s saltinity affects them.
But then why don’t we have dolphins playing in the Mississippi river?
There are types of freshwater river dolphins in the Yangtze (well, one of these species probably is extinct there as of recently but still) and the Amazon, for example. Sea dolphins can survive in freshwater for awhile but their skin isn’t adapted to it, and it will get damaged eventually. That and the difference in buoyancy in sea water vs freshwater leads to the sea dolphins eventually getting exhausted in freshwater.
Not in the Yangtze anymore :(
There is still a bit of the Finless Porpoise left there, but not dolphins specifically no.
They probably cut the fins off to make soup.
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.
Seals and sea lions come up rivers all the time, what matters is the food sources.
