Because this is apparently stick up for wolves day.

Wolf reintroduction in Yellowstone has changed the ecosystem *significantly*.

One remarkable thing that was not predicted that demonstrates how interlinked these things are:

Wolf eat elk.

Elk eat fewer willows.



Willows become healthier.

Number of beavers increase.

Number of songbirds increase.

Overall health of streams increases.

Number of fish increases.

Water table stabilizes.

This is called a “trophic cascade” and we normally see them as bad things. But a positive trophic cascade is an amazing thing, and apparently nobody predicted this one.

What they didn’t predict was that wolf predation would keep elk on the move so they wouldn’t overgraze a specific area.

When the elk overgrazed the willows, they removed the best source of food for beavers during the winter.

Once that stopped happening, the beaver population rebounded and it turns out beavers are pretty good for the entire ecosystem.