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SAN FRANCISCO ESTUARY & WATERSHED SCIENCE Editorial Understanding Central Valley Chinook Salmon and Steelhead: It is Time to Get off the Dime! Randy Brown, Co-Editor-in-Chief San Francisco Estuary and Watershed Science brown.randall@comcast.net BACKGROUND Chinook salmon and steelhead are important biological components of the Central Valley ecosystem. The adults spawn in many streams, the young may spend a few to several months in these streams and in the San Francisco Estuary on their way to the ocean. When the adults return to their natal streams they transfer some of the ocean derived nutrients, organic matter, and energy to the lotic foodweb. Chinook salmon and steelhead together form the basis of economically important com- mercial and recreational fisheries – both in the ocean and inland waters. Chinook salmon and steelhead also are important because they are part of the historic culture in the Central Valley and qualify as “charismatic macro- fauna” with which the public can readily identify. This identification is demonstrated by the Feather River and American River salmon festivals that annually attract thousands of adults and children. The abundances of the four Chinook salmon races (win- ter, spring, fall, late fall) and steelhead are often used to judge the ecological health of the Central Valley ecosys- tem. This judgment is in part because spring and winter Chinook are respectively listed as threatened and endan- gered under the state and federal endangered species acts and the steelhead is listed as threatened pursuant to the federal Endangered Species Act. The late fall and fall runs are federal candidate species. An important ecological objective is to restore habitat and reduce the impacts of other factors so that the two salmon races and steelhead populations recover to the point they can be delisted. To complicate matters considerably, in the Central Valley we have six hatcheries that produce and release all four races of Chinook salmon and steelhead. Five of these hatcheries are mitigation hatcheries – Coleman, Feather River, Nimbus, Mokelumne, and Merced. Two of the hatcheries, Feather River and Mokelumne, also rear and release “enhancement” salmon that are grown specifically to increase the numbers of salmon available to the ocean fisheries. The other hatchery, Livingston Stone National Fish Hatchery, supplements the winter Chinook run. These hatcheries collectively produce and release impres- sive numbers of fish each year: Fall Chinook – 30 million, mostly smolt sized fish, from the five mitigation hatcheries; Spring Chinook – About two million smolts from the Feather River Hatchery; Late fall Chinook – About one million advanced smolts from Coleman National Fish Hatchery; Winter Chinook – About 250,000 advanced smolts from Livingston Stone National Fish Hatchery; Steelhead – About 1.5 million yearlings from Cole- man, Feather River, Nimbus and Mokelumne hatch- eries. Release strategies vary with the race and the hatchery. However, most fall Chinook from the Feather River and Nimbus hatcheries are released off-site in San Pablo Bay,