Watch: Desert rattlers harvest water from their backs

Being able to harvest rainwater on their bodies may help western diamondbacks survive in the arid Southwest. ©Aaron Drew/USFWS

During rainstorms in the desert Southwest, some rattlesnakes, like the western diamondback (Crotalus atrox), emerge to harvest raindrops on the scales on their backs. The snakes flatten their bodies, sometimes forming a tight coil. As the drops coalesce on their back, they suck the water from their scales — an adaptation biologists believe may help them survive in the arid environment.

How does they do it? To find out, researchers dropped water onto the backs of western diamondbacks and two species that don’t show this rain-harvesting behavior — the desert kingsnake (Lampropeltis splendida) and Sonoran gopher snake (Pituophis catenifer affinis). On those snakes, the water formed shallow puddles and slipped away. On the rattlers, the droplets beaded, coalesced and stuck to the scales. Using electron microscopes, the researchers discovered a labyrinth of nanochannels that aided in water collection, and dorsal scales that provided a sticky, hydrophobic surface.

Watch the video below for more, or read the study in ACS Omega.