California Department of Fish and Game
Fisheries Branch
Anadromous Resources Assessment
California Central Valley
Chinook Salmon Escapement
Hatcheries and Natural Areas

The Fisheries Branch Anadromous Resource Assessment Unit compiles annual population estimates of Chinook salmon, Oncorhynchus tshawytscha, in the Sacramento-San Joaquin River system. The GrandTab report is a compilation of sources estimating the late-fall, winter, spring, and fall-run Chinook salmon populations for streams surveyed. Estimates are based on counts of fish entering hatcheries and migrating past dams, carcass surveys, live fish counts, and ground and aerial redd counts. Estimates are provided by the California Department of Fish and Game, the US Fish and Wildlife Service, the California Department of Water Resources, the East Bay Municipal Utilities District, the US Bureau of Reclamation, the Lower Yuba River Management Team, and the Fisheries Foundation of California.

The Sacramento-San Joaquin River system is the principal producer of Chinook salmon caught in California's ocean fisheries. Its salmon runs also contribute to the ocean fisheries of Oregon and Washington. The fall run has been monitored since 1952, spring since 1960, and late fall and winter runs since 1970. The four runs are distinguished as follows:

     1) Late-fall run:  These salmon spawn mainly in the upper Sacramento River and its tributaries near and upstream of Red Bluff. They arrive in this area beginning in October, with spawning occurring from December through April.  Adults of this run are usually larger in physical size than fall and winter-run salmon spawning in the same area.

     2) Winter run:  These salmon spawn almost entirely in the Sacramento River and its tributaries upstream of Red Bluff, arriving as early as December, with spawning occurring from April through August.

     3) Spring run:  Once widespread in Central Valley tributaries, this run has been extirpated from most of the streams in which dam construction has blocked access to upper watershed spawning habitat. Spring-run spawners return to the system from the ocean in late January through August; early arrivals to their natal streams oversummer in holding pools. Spawning occurs from mid-August through October.

     4) Fall run:  These are presently the most numerous and widely distributed salmon in the Central Valley. They return from the ocean during June through November and spawn from early October through late December.

     Monitoring of salmon escapement in Central Valley tributaries is an important component of the California Department of Fish and Game's fishery management function. The primary objectives of this work are to determine size and composition of salmon populations. Changes in salmon abundance, distribution, and habitat conditions that may reflect adverse effects on salmon are noted to determine if corrective action is necessary.

     Thanks to Dick Painter, Bob Kano, and Doug Killam for their work designing and maintaining the original GrandTab.