In the Sierra Nevada, the winter of 2015-2016 was one of the driest on record. During the following summer, a habitat in Yosemite National Park containing Sierra Nevada yellow-legged frogs slowly dried up. Just before the last pools dried, Yosemite mounted a rescue of the tadpoles stranded in the shrinking pools. Several thousand tadpoles were collected and flown via helicopter to a lake upstream in the watershed. This video shows the rescue in action.