In contrast to what biologists had always assumed, sea water Snakes do not drink seawater, and need freshwater in order not to dehydrate.

Now it turns out that sea snakes can drink freshwater after heavy rains, when the rainwater forms lenses or patches on the surface of the seawater.

This is of a low enough salinity for the sea snakes to drink.

Read the full story: University of Florida
Scientific publication: PLoS ONE