This is, flat out, the best book I have read in the last ten years. Skip the rest of this review and go read the book.

Beavers are a keystone species. We need them. Our lives are worse off for having obliterated them from large swathes of North America.

Beavers once inhabited almost all of what is now Canada, Alaska, and the continental United States (except for most of Florida and the southwest deserts). It's hard to pin down an exact number, but the North American population of beavers before the invasion of European settlers was somewhere between 60 million and 400 million. The fur trade had almost made them extinct by the early 20th century. Fortunately, their numbers have recovered to some degree, and they are no longer in danger of extinction.

One problem is that their range has been tremendously reduced. They just don't exist in may parts of North America.

Streams aren't supposed to go in a relatively straight line, rushing downhill until they enter a major river. Streams are supposed to have beaver dams along much of their length. The beaver dams and their associated ponds made streams meander downhill slowly. This reduced erosion, created habitat for many plants and animals, and recharged aquifers, among other benefits.

The book also talks about the troubled relationship between humans and beavers. Most states view beavers as pests and allow them to be killed to eliminate the "problem". The presumption that the land belongs to the humans and any nature that tries to intrude is a problem to eliminate is exactly the attitude that got us into the ecological bind we're now in.

Fortunately, some states are starting to change their attitudes. The book discusses some of the approaches that enlightened humans and governments are taking to try to resolve these conflicts. There is some hope yet.

I can't do justice to the noble beaver and its important role in our ecosystem. Fortunately, Eager by Ben Goldfarb does a masterful job. You should read it.