How was your thankful day? Ours was excellent and in the middle Ben Goldfarb dropped a hard hitting new beaver article on the world, which had such amazing web graphics I was green with envy for a while. I’m almost over it, so let’s enjoy without resentment. The designs of biographic and the academy of sciences are so new and complicated I can’t even share them on this site, so DEFINITELY click on the link this time and go see for your self.
They Will Build It
Although not Indigenous themselves, Alves and Bailey relocate beavers under the auspices of the Tulalip Tribes, a sovereign nation with nearly 5,000 members. This week they’ve set their traps in the Puget Sound suburb of Marysville—half an hour north of Seattle if you leave before daybreak, an eternity at rush hour. Across the street from the Marysville Public Library waits their Silverado pickup, its right two wheels perched on the curb. Alves and Bailey, foreheads damp with sweat, set the beaver down and lower the tailgate. Morning traffic roars past, drivers craning their necks.
“Good?” he laughs. “What good do they do? They’re always clogging up culverts and being a pain in the ass. You’re lucky you got to him before I did.” Before I can craft a response, he snaps up a crushed water bottle and strolls off.
The sentiment that Castor canadensis is little more than a tree-felling, water-stealing, property-flooding pest is a common one. In 2017, trappers in Washington State killed 1,700 “nuisance” beavers, nearly 20 times more than were relocated alive. In neighboring Oregon, the herbivorous rodents are classified as predators, logic and biology notwithstanding. California considers them a “detrimental species.” Last year alone, the U.S. Department of Agriculture eliminated more than 23,000 conflict-causing beavers nationwide.
Running countercurrent to this carnage is another trend: the rise of the Beaver Believer. Across North America, many scientists and land managers are discovering that, far from being forces of destruction, beavers can serve as agents of water conservation, habitat creation, and stream restoration. In Maryland, ecologists are promoting beaver-built wetlands to filter out agricultural pollutants and improve water quality in Chesapeake Bay. In North Carolina, biologists are building beaver-like dams to enhance wet meadows for endangered butterflies. In England, conservationists have reintroduced the Eurasian beaver (Castor fiber) in hopes that their pond complexes will attenuate destructive floods. And in Washington, where a century of habitat loss has devastated salmon, the Tulalip Tribes are strategically dispatching beavers to support the fish so integral to their history and culture.
Back at the truck, I recount my exchange with the beaver-abhorring walker. Alves laughs. She has heard such slander before, and has a rebuttal at the ready.
“I would have asked him if he likes fresh water and salmon.”
You can see right away you’re going to like this article. It’s a great day-after read so I’d gather a second cup of coffee and settle in. Ben is taking us on an journey and you know that’s always somewhere you want to go.
That beavers benefit salmon is, in some quarters, a provocative claim. Many biologists historically regarded beaver dams as stream-choking barriers to fish passage. In the 1970s, Washington, Oregon, and California even passed laws mandating the removal of in-stream wood, beaver dams included. More recently, a 2009 proposal funded by the Atlantic Salmon Conservation Foundation suggested eradicating beavers from 10 river systems on Prince Edward Island and employing trappers to enforce “beaver free zones” in others.
The notion of purging beaver dams to allow salmon to pass, however, doesn’t stand up to scientific scrutiny. One 2016 study documented individual salmonids traversing more than 200 beaver dams on their way to spawn in Oregon streams, suggesting that fish have little trouble negotiating the obstacles. Far from harming salmon, in fact, beavers create indispensable fish nurseries. By filling up ponds and digging canals, beavers engineer the deep pools, lazy side channels, and sluggish backwaters that baby salmon need to conserve energy and evade predators like great blue herons. Today, the National Marine Fisheries Service considers “encouraging formation of beaver dams” vital for recovering Oregon’s endangered coho populations.
“Beavers create complex habitat and enhance local biological diversity in a way that’s really unique,” says Michael Pollock, an ecosystems analyst at the National Oceanic and Atmospheric Administration who’s among the beaver movement’s grandfathers. “They do a much better job of managing these systems than we do.”
Yes they do. Because we get distracted. Beavers don’t. They work like their very lives depend upon these ponds. Which, as it happens, they do. They aren’t working for a paycheck. They’re working to survive.
The white colonists who overran Puget Sound did not share that respect. On January 22, 1855, Isaac Stevens, governor of the new Washington Territory, and dozens of tribal chiefs signed the Treaty of Point Elliott, an agreement that forced many of the Sound’s Native people onto the 22,000-acre Tulalip Reservation. While a judge later called the treaties “unfair, unjust, ungenerous, and illegal,” they did have a redeeming feature, permanently preserving tribal members’ rights to fish at their “usual and accustomed” places. Although the provision was seldom honored—Native fishermen were arrested and harassed, sometimes violently, by their white counterparts—a federal court finally intervened on the tribes’ behalf in 1974, granting Native people half the annual harvest.
Yet the victory was, in some ways, a hollow one. The Puget Sound’s salmon were in freefall, the victims of dams, overfishing, and the Seattle area’s explosive growth. Thousands of acres of marsh had been paved over, hundreds of embayments wiped out. Beaches had been bulwarked, lowland forests demolished. What use was having your right to fish confirmed by the courts if there were no fish to catch? “We’d lost so much natural water storage,” says Terry Williams, the Tulalip’s treaty rights commissioner. “We needed to come up with plans for longer-term watershed recovery, to have natural approaches that allow ecosystems to restore themselves.”
This is a nice way to tell a long story. And if you’re like me you’ll be interested in the human angle of this. The woman to the left of salmon guru Dr. Michael Pollock is his long term girlfriend attorney tribal lawyer enjoying homemade enchiladas at our rental in Santa Barbara during the salmonid conference. Around the table clockwise are Sherry Guzzi, Mike Callahan and Mary Obrien. Because I know these little human details matter to us groundlings.
While expanded ponds are beavers’ most visible hydrologic impact, their ability to recharge groundwater might be an even greater contribution. At the Tulalip’s relocation sites, Ben Dittbrenner has found that for every cubic meter (264 gallons) of surface water beavers impound, another 2.5 cubic meters (660 gallons) sinks into the earth. As that water trickles through the soil, it cools off, eventually reemerging to mingle with streamflows downriver. Elsewhere, such hyporheic exchange between surface- and groundwater keeps streams hydrated later into the dry season, turning seasonal creeks perennial. Dittbrenner’s research suggests that beaver-facilitated cooling and mixing also reduces water temperatures by more than 2 degrees Celsius (about 3.5 degrees Fahrenheit), a huge boon for heat-sensitive salmon and trout.
Although beavers won’t singlehandedly save us from climate change, such findings suggest they might be able to help our stressed water supplies adapt to a warmer future. “By 2100, we’re expecting to see snowpack, which is basically our water storage reservoir, disappear throughout a lot of the Cascades,” Dittbrenner says. “I’m curious whether beavers could make up an appreciable storage component of that lost snowpack.”
The trick to making beavers make a difference is to let them stay around, or encourage them to stay around. Folks do that by planting willow, by not killing them, and by installing BDAs.
So how do you get beavers to cooperate? One option: Give them a leg up. After touring Mahoney, we jounce up yet another endless string of dirt roads to yet another remote tributary, this one shielded from the road by a verdant screen of maple and Devil’s club. The Tulalip had installed beavers here a year ago, with disheartening results. “They just kind of waddled off, never to be seen again,” Bailey says.
To entice the next colony to stay, Bailey and Alves have decided to attempt a new tactic—human-built walls of wooden posts and sticks known as “beaver dam analogues.” The idea behind beaver dam analogues, or BDAs, is simple: In situations where suboptimal habitat discourages beavers from settling down, a human-assisted starter kit can persuade them to stay put and build dams of their own. In one Oregon stream where scientists built more than 120 beaver dam analogues, beaver activity increased eightfold—and juvenile steelhead trout survival spiked by more than 50 percent. Little wonder that BDAs are now among the American West’s hottest stream restoration techniques, deployed to enhance wet meadows for greater sage-grouse in Wyoming, remediate mining waste in Montana, and improve fish habitat in Northern California.
Thanks in large measure to the Tulalip’s example, tribal-led beaver restoration in Washington will soon take another leap forward. Among the volunteers at the beaver dam analogue installation is Erik White, wildlife manager with the Cowlitz Tribe. The Cowlitz’s southwest Washington territory encompasses the Lewis River, which in turn is home to bull trout, a cold-loving fish imperiled by climate change.
“A lot of projections show that 80 percent of bull trout habitat in the Lewis River basin is going to disappear in the next 25 years because of increasing water temperatures,” White says during a break in our post-pounding. Inspired by the Tulalip, he and the Cowlitz Tribe have launched a beaver relocation project of their own, and plan to begin moving the animals to the Gifford Pinchot National Forest in the spring of 2019. “We’ve got less and less snowpack every year,” White adds. “Beavers could be a way to spread flows out into a more natural hydrograph.”
Yes they could. And you know what works even better than moving beavers to a new location and carrying them in cages into remote spaces where you have to drive stakes into the soil just to talk them into to sticking around?
Letting them stay where they choose and dealing responsibly with whatever challenges they cause so you can benefit from them for years to come.
Just sayin’.