How the Beaver is a Superhero

Superheroes fight problems on many fronts, often at the same time. They don’t seek fame or fortune for their efforts, they simply do what they’ve been called upon to do. These larger-than-life characters have considerable impact on the lives of people within their range.

So it is with beavers. They cut trees and build dams, creating wetlands that provide habitat for many birds, amphibians, mammals and fish. The increased biodiversity makes the ecosystem more stable and more adaptable to changes. Beavers are classified as a keystone species, a species that has a disproportionately large influence on the species around it.

Beavers help reduce the impacts of climate change. Water temperatures downstream of beaver ponds are generally a good 4° lower than upstream. As air and water temperatures rise and fish and wildlife experience thermal stress, these downstream cooling effects could make a big difference if enough beaver ponds exist in a region.

Beaver ponds store carbon, keeping greenhouse gases out of the atmosphere. The water table is elevated behind a beaver dam, so oxygen can’t get to much of the wood and other organic matter buried in the sediment. As a result, the wood decomposes much more slowly, releasing far less carbon dioxide. Wood in beaver meadows can last up to 600 years!

Beaver ponds improve hydrologic conditions in several ways. They increase water storage on the surface and recharge groundwater as well. In some places, beaver activity keeps streams running that might otherwise go dry in the summer. As parts of the United States experience more rain and less snow, sudden high-flow events will become more common. Beaver dams slow down the water as it moves through a area, reducing erosion and flooding. Lastly, beaver wetlands serve as natural fire breaks, reducing the likelihood of rapidly spreading wildfires.

In his book, Eager: The Surprising, Secret Life of Beavers, Ben Goldfarb writes that “beavers are ecological and hydrological Swiss Army knives, capable, in the right circumstances, of tackling just about any landscape-scale problem you might confront.”