There are six “distinct population segments” of native steelhead (O. mykiss) in California. Of these, four are listed as threatened; one (the Southern Steelhead) is listed as endangered (significant potential for extinction). The Southern Steelhead evolved in habitat conditions distinct from those of its northern cousins — warmer water, different food sources. Recent studies indicate the Southern Steelhead is genetically older and more pure than their northern brethren.
Historically, there always have been more steelhead populations north of Santa Barbara than south of it. All populations of steelhead in California face a lot of threats. The biggest threat, per the NOAA Fisheries Steelhead Recovery Plans, is migration barriers and dams. Next is a lack of water. In California, virtually all dams were built 50—60 years ago; their shelf life is expiring and many will take a lot of taxpayer funds to keep them safe and operational, pass their re—licensing requirements and comply with the Endangered Species Act.
Taking out the Rindge Dam may be expensive, but it’s not providing any benefit to people any longer, and it continues to impact the ecology and water quality of Malibu Creek — once home to one of the strongest runs of Southern Steelhead. It’s hard to put a price tag on our natural capital. What we do know, once an iconic species winks out and a creek is reduced to a hexagonal flood control channel with a parking lot over it, is that capital can no longer provide as profitable a return.
Drew Irby
Trout Unlimited, South Coast Chapter