How Wolves Change Rivers. (Video) 

When wolves were reintroduced to Yellowstone National Park in the United States after being absent nearly 70 years, the most remarkable “trophic cascade” occurred. What is a trophic cascade and how exactly do wolves change rivers? George Monbiot explains in this brilliant video remix made by Sustainable human...One-to-follow!  WATCH HERE…. The narration is excerpted from a TED talk by George Monbiot – watch it here.