12300'W 



12230' 



3800'N - 



SAN 

 1-RANCISCO * 



3730' 



A Chinook salmon (Oncorhynchus tshawytcha). Most chinook salmon found in the Gulf of the Farallones are 3-year-old fish that are returning 

 from the open ocean and preparing to enter the Sacramento River system, where they will spawn and then die. (Photograph from U.S. Food 

 and Drug Administration.) 



As shown in this simplified diagram, 3-year-old chinook salmon return- 

 ing from the open ocean move into the Gulf of the Farallones in 

 February and March and feed on Pacific herring and anchovies off the 

 Golden Gate from Bolinas Point in the north to Point San Pedro in 

 the south. In April, they feed on invertebrates, largely the euphausiid 

 shrimp (krill) Thysanoessa spinifera. For a brief 2- or 3-week period 

 in April, the chinook salmon's diet is dominated by larvae of the 

 Dungeness crab (Cancer magistei). In May and June, chinook salmon 

 start feeding on krill and juvenile rockfish near the Farallon Islands. 

 Sometime between mid-June and mid-July, chinook salmon abruptly 

 move from near the Farallon Islands to directly in front of the Golden 

 Gate, the so-called "middle grounds." Here, chinook salmon feed 

 exclusively on anchovies. Chinook salmon remain in front of the Golden 

 Gate until October, but in lower and lower concentrations as they move 

 up the Sacramento River system to spawn. The following February, the 

 next year's 3-year-old chinook salmon begin to enter into the gulf, and 

 the cycle begins again. 



Chinook salmon fishing is the activity that brings the 

 most people out on the waters of the Gulf of the 

 Farallones. This large salmon was caught in the gulf. 

 (Photograph from National Marine Fisheries Service.) 



Salmon 43 



