The results from recent work at the confluence of Deer Creek and the Lower Yuba River mean good news for spawning Central Valley Chinook salmon, according to scientists at the Nevada City-based non-profit Sierra Streams Institute.
Survey results show a four-fold increase this year in the number of salmon redds, or nests, compared to last year in Deer Creek’s critically important habitat reach, one of the final spawning areas before fish passage is blocked by Englebright Dam, according to a Friday news release issued by Sierra Streams.
Sierra Streams Institute received grant funding to improve conditions for spawning salmon from Bella Vista Foundation, a San Francisco-based foundation that funds ecosystem restoration work in California and Oregon.
Throughout the month of September, the nonprofit’s scientists and their partners removed large rocks that armored the streambed and prevented spawning,and placed 250 tons of suitably sized gravels and small cobbles that are needed by spawning salmon to build their redds, the release states. Upstream dams now block these naturally occurring gravels.
Yuba Blue Boulders owner Ralph Mullican granted crucial access to the creek for the work and provided heavy equipment and expertise, the release states. The project was designed in consultation with Mullican and CSU Sacramento Professor Tim Horner.
Justin Wood, project manager and river scientist at Sierra Streams Institute, continues to monitor the arrival of spawning salmon and notes that about 90 percent of this year’s spawning activity has occurred in the three areas of the spawning reach that were restored in this project.
Salmon and other anadromous fish — species that live their adult lives in the ocean but move into freshwater streams to reproduce — are threatened all over the west because of dams, as well as degradation of habitat and water quality. Because Englebright Dam now blocks much of the Yuba River’s historic spawning range, restoration of Deer Creek’s spawning habitat is a critical part of efforts to reverse years of population declines.