since the early 1860s. By the 1890s, annual landings exceeded 2,300 t. Bycatch problems related to shrimping have led to fishing restrictions. Today the catch is down considerably from the peak years, and the shrimp is now sold mainly for bait (Leet et al. 1992).
Dungeness crab (Cancer magister) used to be commercially important in San Francisco Bay. Bay-area landings reached more than 3,500 t in 1956–1957 but have been less than 450 t during most years since. The fishing fleet in the bay area has been halved since 1957. The reasons for the collapse are not precisely known but probably include bay pollution, predation by nemertean worms, and changes in ocean temperature (Leet et al. 1992).
A total of 432 striped bass (Morone saxatilis) from the Navesink River in New Jersey were deliberately introduced by the U.S. Bureau of Commercial Fisheries to San Francisco Bay in 1879 and 1882, along with American eels (Anguilla americanus), American lobsters (Homarus americanus), and other species (Lampman 1946). Although the lobsters and eels did not become established, the striped bass did, soon supporting major commercial and recreational fisheries. By 1899 more than 540 t of bass were commercially harvested (Skinner 1962). Striped bass have become established from approximately Monterey Bay, California, to Coos Bay, Oregon, with occasional fish being found as far south as northern Baja California, Mexico, and as far north as southern British Columbia, Canada (Hart 1973, Moyle 1976). The growing competition between recreational and commercial fisheries resulted in the banning of commercial fishing in 1935. Despite a gradual decline in striped bass populations, the sports fishery was still valued at $45 million in 1985. The populations in San Francisco Bay have continued to decline (California Fish and Game Department 1997), probably because of many factors, including water diversion, a changing food web caused by invasive species, and pollutants, although knowledgeable anglers continue to catch fish.
The commercial fishery for the longed-lived white sturgeon (Acipenser transmontanus) was quickly exhausted. During 1887, more than 680 t was caught. The catch dropped to 136 t by 1895, and the fishery was closed in 1917. Freshwater flow into the bay is apparently important for recruitment in this species as well (Leet et al. 1992).
Never a favored fish commercially in this region, Pacific herring (Clupea