The Beaver, the Salmon, the River, and the Forest: Protecting California’s Intricate Ecosystems
In the opening pages of The Forests of California, author Obi Kaufmann describes two essential characters within California forests: the beaver and the salmon. Kaufmann explains how, in their long journey to the ocean and back, the salmon provides more critical nutrients to the environment than any other being. He also shows us how the beaver shapes habitats and creates the right conditions for abundant biodiversity, including salmon populations.¹
As I read about these two connected creatures, I was struck, as I often have been, by how interrelated and interdependent our forest ecosystems are. The beavers, the salmon, the forests, and the rivers are all critical to each other — each impacts the other, and we need all of them to be healthy for our ecosystems (and human communities!) to thrive.
The Beaver and the Salmon
By building dams, beavers create flooded wetlands with deep water reserves. As the California nonprofit Beavers & Brush points out, these creatures keep nine times as much water running through the ecosystem just by making their homes. Not only do beavers keep streams flowing throughout the year, but they also mitigate erosion, improve water quality, and support abundant biodiversity. Dams and the water channels carved by beavers purify the water and leave more stable stream banks. These natural engineers create a wetter, more stable environment that allows plants and animals to thrive — including humans. In fact, some argue that beavers are actually some of our best firefighters in California (check out this Sierra Club Magazine article, or this webpage from Beavers & Brush).
The beaver’s activity in rivers and forests creates the right conditions for the salmon to thrive. Beaver ponds are deep enough to stay cool in the sun, and (according to this great article published recently in Smithsonian Magazine) they increase the amount of water available in summer months by 20%. Salmon need cool, clean water to breed — so beaver-engineered habitats are perfect for a juvenile salmon nursery, and can help support the population numbers that salmon need in order to face their treacherous journey from mountain to sea and back again.
These special fish, in turn, provide vital nutrients to the entire ecosystem. Pacific salmon all generally follow the same life cycle: birth in freshwater habitats, a migration downstream to the ocean, and an upriver return to their spawning grounds to reproduce and die. As noted in a recent BioScience paper, during their time at sea salmon will gain over 90% of their biomass. As they return, the breakdown of their biomass results in a huge input of critical nutrients like phosphorus, nitrogen, and calcium. These nutrients feed the plant life, from meadow vegetation to trees, and in this way these fish feed the whole ecosystem.
Our Human Role: Defending Healthy Forests
The role we humans can play in conservation is always nuanced and evolving. But one thing that is simple enough to get right is keeping our forests healthy and intact, in order to support the myriad creatures, relationships, and cycles that they contribute to.
In California, we’re trying to save our forests by stopping the practice of clearcutting, a destructive logging method that replaces healthy, natural forests with man-made timber plantations. This unsustainable practice is putting our wildlife and our watersheds in danger — and it’s happening every day.
The forest shares many ecosystem functions with the beaver: restoring water supplies, fighting erosion, and supporting wildlife habitat. Our forests and our wildlife are critical for healthy ecosystems, economies, and human communities — yet more than 30% of California’s species are threatened with extinction. As of 2017, California’s Chinook, Coho, and Steelhead salmonids — fish that have lived in the state’s rivers for millions of years — have all been classified as at risk for extinction.²
Clearcutting is one of the key reasons that wild salmon and other wildlife populations in California have dropped. This indiscriminate logging method warms and pollutes the rivers: a recent study has shown that the more clearcutting there is, the more sediment pollution there is in the water. Toxic herbicides used in clearcutting can also make their way into our watersheds and fisheries, further polluting waters that healthy forests help keep clean. Clearcutting ultimately reduces our supply of clean water, too — an urgent matter, given that we rely on our forests to supply 75% of our water in California.
Based on data obtained from CAL FIRE, more than 50,000 acres of California forest are being clearcut every year. We must choose more sustainable logging methods. We must reject the destructive practice of clearcutting in order to defend our complex forest ecosystems — ecosystems that support terraced beaver marsh habitats, the wriggling bundle of vital nutrient cycling that is the salmon, and the clean, connective water that our river veins provide.
“Through a deep ocean of time, in the evolved matrix of forces that influence our modern forests, made up of untold numbers of interfacing systems, we find a biological super-entity whose complexity rivals any terrestrial, cosmological, or biological process we know…with the advent of this age of climate breakdown, the best policy we can negotiate is the restoration and conservation of as much as we can of the hundreds of square miles of intact forests that still exist…” ³
Without healthy forests, we lose the beautiful relationships between the trees, the beavers, the salmon, and the rivers — and our human world becomes less stable.
[1] Obi Kauffman, The Forests of California (Berkeley, Heyday, 2020), 23.
[2] Kauffman, The Forests of California, 30.
[3] Kauffman, The Forests of California, 34.