A team of civil engineers in Washington state is using beavers to help mitigate some of the effects of climate change. The beavers are being relocated to the upper reaches of the Skykomish River, where they are boosting water storage and lowering stream temperatures. This indicates that
In just one year after their arrival, the new recruits brought average water temperatures down by about 2 degrees Celsius and raised water tables as much as about 30 centimeters, researchers report in the July Ecosphere. While researchers have discussed beaver dams as a means to restore streams and bulk up groundwater, the effects following a large, targeted relocation had been relatively unknown.
Water storage is critical during drier periods because it can keep the ecosystem resilient to droughts and fires,” says Emily Fairfax, an ecohydrologist at California State University Channel Islands in Camarillo who was not involved with the study
The Skykomish River flows down the west side of Washington’s Cascade Mountains. Climate change is already transforming the region’s hydrology: The snowpack is shrinking, and snowfall is turning to rain, which drains quickly. Waters are also warming, which is bad news
The beaver-wetlands also act as sponges, soaking up floodwaters and releasing them gradually. Beavers are often considered one of the keystone species in an ecosystem. Their dams and ponds can create habitat for many other species of animals, fish and plants
In 2014, aquatic ecologist Benjamin Dittbrenner and colleagues relocated 69 beavers (Castor canadensis) from lowland areas of the state to 13 upstream sites in the Skykomish River basin, some with relic beaver ponds and others untouched. As beavers are family-oriented, the
The researchers also found that singletons were just as successful as couples in building dams and lodges. “They were not picky at all,” says Dittbrenner, of Northeastern University in Boston. Fresh
At the five sites where beavers were introduced, they built 14 dams over the course of a year. These dams caused the volume of surface water (streams, ponds, wetlands) to increase by 20 times. Additionally, the groundwater at three of these sites increased to more than twice the amount that was stored on the surface in ponds. Stream temperatures downstream of the dams fell by an average of 2.3 degrees C, while streams not subject to the beavers’ tinkering warmed by 0.8 degrees C.
We're achieving our restoration objectives much faster than we thought possible, which is great news," Ditt
temperate enough to almost completely remove the streams from the harmful range for salmon during a particularly hot summer. “These fish are also experiencing heat waves within the water system, and the beavers are protecting them from it,” Fairfax says. “That to me was huge.
Beavers are known for their engineering feats, which include building dams that can transform rivers into sprawling lakes. But a new study suggests that these creatures may also have a hand in mitigating climate change. The study, published in the journal Nature Communications, found that beaver ponds can help regulate stream temperatures, potentially providing a buffer against the effects of global warming. Beaver ponds are created when the animals dam up streams with branches and mud