How Wolves Change Rivers

"When we try to pick out anything by itself, we find it hitched to everything else in the Universe." - John Muir

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 movie remix.

Comments
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billso
billso

"An ecological process that starts at the top of the food chain.. tree heights quintupled...". This is fascinating. The story of the wolves' return was broadly covered, but not the downstream effects. I had no idea.

ChrisAgnos
ChrisAgnos

Editor

@Jack16 That's so true. It's almost like every species is a piece of a larger, more intricate puzzle.

Jack16
Jack16

@pete I think they probably understood the basic idea of the "trophic cascade", but it seems like they didn't expect it to be as impactful as it was. I agree though, it is so cool how one little balance to an ecosystem can alter so much in a positive manner.

pete
pete

This is really interesting. Were the positive effects on the ecosystem a surprise to the people who made the decision to reintroduce the wolves? Either way, so cool!

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