Nature: Leave It To Beavers [2014 TV episode]

A growing number of scientists, conservationists and grass-roots environmentalists have come to regard beavers as overlooked tools when it comes to reversing the disastrous effects of global warming and world-wide water shortages. Once valued for their fur or hunted as pests, these industrious rodents are seen in a new light through the eyes of beaver enthusiasts who reveal the ways in which the presence of beavers can transform and revive landscapes.