Surrounded by salty water, sea snakes sometimes live a thirsty existence. Previously, scientists thought that they were able to drink seawater, but recent research has shown that they need to access freshwater. A new study published in PLOS ONE on Feb. 7 and led by Harvey Lillywhite, professor of biology of the University of Florida, shows that sea snakes living where there is drought relieve their dehydration as soon as the wet season hits, and do so by obtaining freshwater from “lenses” that form on the surface of the ocean during heavy rain—events in which the salinity at the surface decreases enough for the water to be drinkable.
The yellow-bellied sea snake (Hydrophis platurus) is the only reptile in the order Squamata that lives on the open sea. It has one of the largest geographic ranges of any vertebrate species. Given its broad range and seafaring existence, during the dry season (6-7 months at the study site in Costa Rica) it has no access to freshwater. How they survive in regions of drought seems to hinge upon access to freshwater lenses, but little is known about how marine vertebrates react to or consume rainfall. “This study contributes to a fuller understanding of how pelagic sea snakes, and possibly other marine animals, avoid desiccation following seasonal drought at sea,” said Lillywhite.
Read more at University of Florida
Image: The yellow-bellied sea snake is the only pelagic species in the order Squamata (snakes and lizards). CREDIT: Mark Sandfoss