JACKSON, Wyo. — After an extensive history of fur trapping that decimated the beaver population in the U.S., there’s good news for the keystone beaver population in Jackson Hole.
The Wyoming Game and Fish Department (WGFD) defines a keystone species as one that has a disproportionately large effect on their environment relative to their abundance, and confirms beavers fall under this categorization due to their critical role in North American watersheds.
According to Cody Pitz, wildlife biologist and beaver restoration program coordinator with Wyoming Wetlands Society (WWS), beavers are one of the most significant local species. Pitz tells Buckrail that beavers create some of the largest areas of ecosystem in the region, taking a small stream and making it into a several acre pond.
Beavers shift the landscape by building dams, primarily forming the larger, deeper ponds for their own safety; beavers use the water depth they create to hide from predators. But the impact of the pond is huge, with Pitz suggesting that beaver ponds have similar biodiversity to coral reefs and tropical rainforests. The ponds are able to support trout populations, moose, sage grouse chicks who need nutrients, ducks, swans and more.
“I think I consider beavers the keystone species,” Pitz says.
Beavers create riparian habitat, meaning habitat that occurs along the edges of water, which Pitz says 80 percent of wildlife species in Wyoming are dependent on. While WGFD also confirms this statistic, they note that less than four percent of Wyoming’s land area actually consists of riparian habitat, which drops to less than one percent in the entire western landscape.
Since 2004, WWS has been operating one of only a small handful of active beaver facilities in the U.S. Live-trapped beavers are processed and held in the facility until they can be relocated, ideally as a family group, to a permitted area where they can continue making wetlands, preserving water, creating wildlife habitat and mitigating the consequences of climate change like flooding.
Pitz says the goal is to restore beavers to their historical densities where they were historically present. And he says between the work WWS is doing and his own field observations of beavers moving and expanding, the local beaver population is trending in a generally positive direction.
Pitz suggests some of that population growth has to do with the fact that trapping for furs is less profitable than it used to be. According to the Fur Market Report from December 2022, the average price that a trapper can get for an entire beaver pelt is between $10 and $15. While recreational trapping has the potential to wipe out several colonies, Pitz says it won’t reduce the numbers like fur trapping did in the 1800s.
But beavers still face risk due to a warming climate. Pitz says they’re very sensitive to heat, although they’re also effective at managing the risk of overheating because they live in water. But if a stream were to completely dry out due to drought, it could cause the beaver colony occupying that habitat to die.
As recently as September, Pitz and his coworker witnessed an area in Big Piney that used to have a robust beaver population affected by drought, with all the streams dried up and no surviving beavers.
Additionally, predation is a big risk in Jackson Hole. Wolves, bears and mountain lions prey on large quantities of beaver; Pitz notes hearing about a mountain lion researcher in the area who found 80 beaver carcasses from one female lion in a single season.
Considering both the risks to beaver populations and the significant ecological work they do, the WGFD urges landowners to relocate these habitat builders only as a last resort.
“Many landowners may find the benefits of keeping beaver outweigh the inconveniences,” WGFD writes on their website.
Pitz agrees that a big misconception is that landowners have to remove beavers from their property to prevent property damage. He suggests fencing trees, especially beaver favorites like aspens and cottonwoods, to effectively mitigate beaver damage. Additionally, the WGFD recommends installing culvert protection devices, installing a “beaver deceiver” flow regulation device and physically removing a dam. The WGFD notes that it may take multiple dam removals to convince a colony to move on.
The importance of beaver behavior is not only tied to other wildlife species, but benefits humans as well. Beavers can mediate stream temperatures as the climate warms and preserve more and larger fish populations, reduce flooding, preserve water on a landscape where it would otherwise run off and establish natural fire breaks.
All this work, Pitz points out, beavers also do for free.
