Wednesday January 4, 2023
Eos —
Beavers are among the world’s most effective engineers. Members of this keystone species build dams and canals and, in so doing, create entire, multilayered wetland ecosystems. Beginning in the 1600s, however, the fur trade decimated North American beaver populations.
The species began rebounding in the early 20th century but sometimes came into conflict with the agricultural landscape, as by the 1940s and 1950s, people were aggressively modifying streams to maximize yield. Returning to their former haunts meant persecution as beavers flooded crops and felled orchards, explained Alexa Whipple, program director for the Methow Beaver Project (part of a nonprofit called the Methow Salmon Recovery Foundation).
Now, humans are starting to recognize that beavers, though still considered pests by some, benefit landscapes in myriad ways. For instance, beaver activity can reduce erosion, create habitat for other species, and maintain wetlands.
In fact, we often want beavers to move back into landscapes to do the engineering for us, said Emily Fairfax, an assistant professor at California State University, Channel Islands. “But how are we going to know if they are doing that,” she asked, “if we don’t even know where they are?” The answer lies in remote sensing imagery, which can help scientists identify the landscape-scale features created by beaver families.