Avery Schaller

So wildlife ecologist Avery Schaller says after the wolves came back... The story goes that wolves impacted the density or behavior of elk so much that the effects cascaded, trickled down to aspens and willows, which affected...

beavers and songbirds and eventually change the course of the rivers.

When you get this kind of tunnel vision on single species conservation, it can really ignore other bigger threats to wolves and other species that also matter.

But there's a lot of good people involved.

doing a lot of the work in the middle.

And ecology is really complex.

And we're still in the early stages of seeing exactly how wolves impact the Yellowstone ecosystem.