Another block buster from our friends at the science site that should be called “Beaver Phys.org”. This morning the news has also been picked up by plenty of followers including “New Scientist”. Because beavers are just rock stars like that, you know?
Yes beaver dams lower the temperature for sweaty fish. We here at beaver central have been touting this fact for years. Pollock proved it years ago, but now it’s especially even more extra proven. Has any creek been the subject of more study than Bridge Creek? I doubt it.
The researchers found that beaver dams may alter stream temperatures to the benefit of salmonids. Studies suggest that juvenile steelhead salmonids in Bridge Creek experience extreme stress at about 25°C, and the researchers found that maximum daily temperatures in much of the study stream exceed this temperature for much of the summer. However, temperatures rarely exceeded 25°C after the proliferation of beaver dams, likely because they help moderate temperatures both by increasing water storage and encouraging exchange between surface water and groundwater exchange. This fits with the fact that both beavers and salmonids were once more abundant and widely distributed in North America, and suggests that beaver dams could help mitigate the thermal degradation that can threaten sensitive species.
Dr. Weber notes: “Beaver are often considered a keystone species, and their propensity to build dams plays an integral role in maintaining biodiversity and enhancing aquatic processes that benefit an array of aquatic and terrestrial organisms. Recognizing this, beaver relocation efforts and installation of structures designed to mimic the form and function of beaver dams are increasingly being used as effective and cost-efficient approaches for restoration of stream and riparian function. Despite this trend, the notion that beaver dams negatively impact stream habitat remains common, specifically the assumption that beaver dams increase summer stream temperatures to the detriment of cold-water species such as trout and salmon. However, by tracking beaver dam distributions and water temperatures throughout a high-desert, scientists have demonstrated that beaver dam can actually reduce high stream temperatures by increasing surface water storage and connectivity with cool groundwater. These results suggest that construction of artificial beaver dams and beaver relocation projects could be used to mitigate the impact of human induced thermal degradation that may threaten sensitive cold-water species.”
If you need the reference to go look up it’s here. Feel free to notice how many of the names are friends of this website.
Weber N, Bouwes N, Pollock MM, Volk C, Wheaton JM, Wathen G, et al. (2017) Alteration of stream temperature by natural and artificial beaver dams. PLoS ONE 12(5): e0176313. doi.org/10.1371/journal.pone.0176313
Dr. Wheaton wrote yesterday to make sure I saw it, but three beaver readers had beat him to it. Let’s hope all those backwards thinkers in Wisconsin who rip out beaver dams to protect their baby trout read it and at least think, huh??? Maybe they’ll even start to read the research later than the 1970 study they tuck under their pillows at night.