This report arrived recently on the Scott’s river salmonid recovery and is full of encouraging things, But I especially loved the Michael Pollock quote. See if you can tell why:
People started building artificial beaver dams in California. Now something “mind blowing” is happening
Following the construction of the dams, one river saw juvenile coho salmon survival rates soar from 8% to 60%.
It’s well known that beaver dams transform landscapes. In their absence, artificial versions were built in northern California to recreate lost wetlands – boosting the survival of threatened coho salmon.
The findings are published in Frontiers in Ecology and Evolution. Fish biologist Michael Pollock of NOAA’s Northwest Fisheries Science Center called the results “mind blowing”.
Well, Pollock is the one who has been researching this all along, so if he says the results are mind blowing I think we should believe him.
With the beavers all but gone, in 2015 the nonprofit Scott River Watershed Council built two artificial dams on a tributary called Sugar Creek. Wooden posts were hammered into the streambed, interwoven with willow and conifer branches, then the gaps were plugged with gravel, straw and mud.
Three years later, several more dams were built on another tributary, called French Creek. From time to time, the remaining beavers even chipped in, repairing, modifying and sometimes expanding the dams. “When beavers do adopt a structure, their work is far superior to what we can accomplish,” says Charnna Gilmore from the Scott River Watershed Council.
Small, low-cost interventions yielded big, impressive results. But it’s bittersweet. “My take is that the artificial dams have helped people remember what the beaver can do and how integral they are to the health of stream ecosystems,” says Pollock. “But beavers can only thrive if landowners allow them to.”
