There's a really good book about a homesteader that did something similar to this in the 1930's in British Columbia, "Three Against The Wilderness". Basically he restored the dams that had been dynamited by the ranchers, and that restored all of the wetlands in the area.
Later on, the government brought him some beavers from elsewhere, and they flourished.
I love this. Especially the part where you can ask the Government of Canada for beavers.
But it feels like there’s a bit of surprise to the idea that the environment takes on the form it takes on. And if you take away a part of it, it’ll take on a different form. And if you put that part back, it can take on the earlier form. There is no correct or canonical form.