Scientists Acquire More Proof That Only Beavers Can Save the World
The modern 21st century pillaging of Western watersheds by private for-profit companies like Nestlé, who are guzzling millions upon millions of gallons of municipal water, in tandem with ecologists who say the near extinction of Castor canadensis from parts of the West in the 19th century; have come together to cause these two great mishaps to magnify the effects of California’s worst dry spell since the of the era of irrigation began.
As the U.S. expanded westward beavers were nearly eradicated by humans because they were interfering with our logging and fishing industries. But that’s exactly why beavers need to return. Rivers and streams that have been diverted by humans are designed to remove water quickly from the watershed, destroying local habitats for animals and making it more difficult for an ecosystem to recover from drought.
“Beavers create shock absorption against drought,” says Brock Dolman, a scientist in Sonoma County who wants to repopulate coastal California with the big lumberjacking rodents. Beavers build infrastructure which help to slow the flow of water, letting it recharge local aquifers, and preventing erosion which helps keep plants alive.
“Beavers aren’t actually creating more water, but they are altering how it flows, which creates benefits through the ecosystem,” says Michael Pollock, an ecosystems analyst and beaver specialist at the National Marine Fisheries Service Northwest Science Center.
Seeing how beavers can help to save California from its seemingly endless drought, it also looks like they can save the world from industrial farming by changing the chemistry of the water, making them natural biochemists. For quite some time, the world starved for nitrogen. It’s a necessary component for life, and essential for growing crops. Nitrogen makes up most of the atmosphere around us, but getting it out of the air and into the soil could only be done by certain plants and creatures. As nitrogen was sucked from the soil, crop land grew less and less productive and people went hungry. The discovery of nitrogen fixation — grabbing nitrogen from the air and putting it into fertilizers — has saved billions of people from starvation.
The algae use up the oxygen in the streams, the rivers, and eventually parts of the ocean, leaving nothing for the fish and leading to large “dead zones.” Biologists at the University of Rhode Island were studying the nitrogen content of streams and noticed something odd: whenever there were beaver ponds upstream, nitrogen levels dropped. Beaver ponds slow down river water, and they mix it with organic matter, which must have an effect on river chemistry, but scientists didn’t know exactly what was happening in that murky water.
So they made soda-bottle-sized “ponds” that let them study variations on the conditions the beavers set up in their real-life ponds. And they found a kind of reverse nitrogen fixation process was occurring — call it “denitrification.” Bacteria in the dirt and the plant debris turned nitrates into nitrogen gas. The gas bubbled up to the surface and mixed with the atmosphere once more. In some cases, the level of nitrogen in the water dropped 45%.
The effect was most pronounced in small streams, which lead to bigger rivers and eventually to the ocean. Beavers often set up their homes in these tiny streams—or they did before they were trapped or driven away. Re-introducing them might completely change downstream chemistry, make these environments more livable not just for the beavers, but for their fellow creatures, too.