A World Without Beavers Is a World Without Wildlife We Love

The buck-toothed mammals are the best ecosystem engineers nature has to offer. Ben Goldfarb's exhaustive new book explains why.

Leave it to beavers . . . to fix the environment for us.

For millennia, Castor canadensis have shaped landscapes with their dams, turning scrub into meadows and flood waters into wetlands. But the rodent’s role has long gone unappreciated. So unappreciated that in the late 1800s, beavers nearly went extinct in the United States and Canada due to decades of fur trapping and extermination. The European species faced a similar plight, dropping to just 1,200 individuals around the same time.

But now beavers are back with a furor—to the benefit of humans and countless other species. Take it from Ben Goldfarb, science journalist, Audubon writer, and author of the new book Eager: The Surprising, Secret Life of Beavers and Why They Matter.

Once the 1900s hit and the fur trade went out of vogue, the Castor population rocketed; today, there are an estimated 15 million beavers in North American waterways. But rather than allow them to thrive in pockets, experts have schemed up ways to move them to areas that are badly in need of beaver engineering. In 300-plus fact-packed pages, Goldfarb traces these reintroduction projects with outrageous anecdotes of parachuting animals, Beaver Deceivers,” and cloaca milking. He also demonstrates how civilizations, ecosystems, and corporations like Walmart are tied to the mammal’s wellbeing. One example follows the Tulalip Tribes in Washington, which use dams to channel snowmelt and runoff into salmon streams during spawning. (The fish is an integral part of the community’s culture and economy.) On the opposite coast in Acadia National Park, Goldfarb points out that the reintroduction of beavers has close to doubled the percentage of wetlands over a 53-year span. As one of the fastest-declining habitats, wetlands everywhere could use this kind of a boost.

And then there are the beaver-loving birds. Trumpeter Swans, which have faced their own up and downs across North America, like to stack their 11-foot nests on top of the rodents’ fortresses. Farther west, Greater Sage-Grouse sip at beaver meadows, and Yellow-billed Cuckoos seek shade in cottonwoods, watered by their fat-tailed friends. In total, beavers are credited for enhancing bird diversity on three different continents. Without them, the forests would be less musical, and birding would be way more frustrating.

That said, there are plenty of folks who still think beavers are a nuisance. With Eager Goldfarb sets out to quash old misconceptions, including the tacky Castor portrayals we see in pop culture. (Thankfully, he spares my favorite college drink: the Bionic Beaver, a concoction of Busch Light, Hawaiian Punch, Sprite, and bottom-shelf liquor, served on the rocks, in a pitcher, at Teds in Storrs, Connecticut.) But more importantly, he brings the mammal’s merits to light.

Appreciation is the key to keeping beavers—and everything they've built—around in the landscape. When we don't understand our most common creatures, our world becomes smaller; we lose sight of nature's complexity and all that's irreplaceable. “While organisms have evolved to fill niches provided by nature, neither beavers nor people are content to leave it as that,” Goldfarb writes. “Instead we’re proactive, relentlessly driven to rearrange our environments to maximize its provision of food and shelter. We aren't just the evolutionary products of our habitat: We are its producers.” These are the words of a true beaver believer.

Eager: The Suprising, Secret Life of Beavers, by Ben Goldfarb, Chelsea Green Publishing, 304 pages, $24.95. Buy it online at Chelsea Green.