http://www.sciencemag.org/news/2020/05/bizarre-behavior-shows-first-time-how-wild-koalas-drink

Koalas begging firefighters for water have become emblematic of Australia’s recent wildfire woes. But aside from these unusual interactions, scientists have never been quite sure how koalas drink. Now, a new study has documented the first evidence of the clever way they stay hydrated: by licking water from the smooth bark of gum trees as it rains.

Past research has suggested that because koalas spend the vast majority of their time in trees, they likely get most of their water from the eucalyptus leaves they eat. But over the course of 7 years—from 2006 to 2013—citizen scientists, ecologists, and landowners reported 46 sightings of tree-licking behavior (above) in wild koalas. Researchers reviewed video and photographic evidence, and they found that even when puddles or lakes were nearby, koalas were more likely to drink the water running down trees, they report this month in Ethology.