GOBALET, K. W.: Archaeological Evidence for Steelhead Oncorhynchus mykiss in the Coastal Streams of California from San Francisco to Mexico

Southern populations of salmon and trout (family: Salmonidae) are in dramatic decline. Conservation and legal issues surround whether or not salmon and trout are native to coastal streams of California. Since authoritative surveys of the California streams prior to the 1890’s are nonexistent, the archaeological record is an important source for addressing such questions. In this study data from close to 100 archaeological sites from San Francisco to the Mexican border were analyzed along with numerous inland sites. Discriminating between species of the family Salmonidae, even when bones are intact is challenging. No salmon remains have been recovered from coastal middens south of San Francisco, but steelhead rainbow trout Oncorhynchus mykiss were found in all coastal counties south of San Francisco except San Mateo, Ventura, and Orange. With the exception of archaeological sites on the eastern borders of the San Francisco Bay, salmonid representation is poor in coastal and inland sites. This is perhaps a function of poor preservation. No salmonid remains at all have been found in archaeological sites in the Central Valley south of San Joaquin County and Sacramento perch (Archoplites interruptus) are the single most abundant species identified from inland sites.