Coho salmon are blinking out rapidly across their range. In California’s central coast, the situation is particularly dire. Once abundant native populations have declined to the point where artificial propagation may be the species’ only chance for survival. Loss of freshwater habitat has been identified as a severe threat to the survival of Coho. According to the National Marine Fisheries Service, over 90 percent of remaining freshwater habitat for salmonid species in California occurs on privately held forestlands.
In the Ten Mile River, Mendocino County, Coho salmon appear to be hanging on by the skin of their teeth. Data from the Ten Mile is unfortunately scarce. However, it is clear that Coho populations have declined. Historic and current land use activities have resulted in substantial loss of spawning and rearing grounds for Coho in the Ten Mile through excessive sedimentation. In 1998, the Ten Mile was listed as impaired under Section 303(d) of the Federal Clean Water Act due to excessive sediment. Over 85 percent of the Ten Mile River basin is owned by Campbell Timber Management Company.
Campbell Timber Management’s logging regime in the Ten Mile consists of high intensity practices, including clearcut logging, road building on steep and unstable slopes, and the use of herbicides. For many sub basins in the Ten Mile, Campbell’s intensive management includes an extremely high and intensive rate of harvest. The Department of Fish and Game (DFG) has recently inspected proposed logging operations in two sub basins in the Ten Mile and found that Campbell’s rate of harvest in these sub basins far exceeded levels where salmonid habitat simplification is known to occur. DFG recommended that Campbell eliminate clearcutting from these logging plans in order to mitigate the rate of harvest. Recently, a report prepared for the Regional Water Quality Control Board, documented that excessive fine sediment generation and transport that impact salmonid habitat was positively correlated with the amount and the intensity of harvest in a given watershed (Klein et al. 2008). In a letter written by DFG to the Santa Rosa Review Team, Klein’s research was cited when raising concerns over rate of harvest in the Ten Mile. Rate of harvest, is how much of a watershed is harvested in a given period of time.
Campbell has responded to these concerns by hiring its own scientist in an effort to refute the research of Klein et al. Campbell claims that the research isn’t applicable to their operations, and has defended their intensive approach to forest management, and Campbell continues to refuse to change their logging operations as recommended by DFG. Meanwhile, Cal Fire has unsuccessfully scrambled to poke holes in the DFG’s arguments and the Klein et al. research. Thus far, Cal Fire has not moved to approve these logging plans, and other responsible agencies such as the National Marine Fisheries Service and the Regional Water Quality Control Board do not appear to have any current plans to intervene.
For the Coho, the outcome of battles such as this could determine long-term survival in the Ten Mile.
Klein, R.D., Trush, W.J., Buffleben, M.S., 2008. Watershed Condition, Turbidity, and Implications for Anadromous Salmonids in North Coastal California Streams. Report to North Coast Regional Water Quality Control Board, Santa Rosa, CA. http://www.waterboards.ca.gov/northcoast/publications_and_forms/available_documents/pdf/Turb_Rpt_Final_5_21_08.pdf