Fish Bulletin 147. The Northern Anchovy (Engraulis Mordax) And Its Fishery 1965–1968
In 1964 scientists of the California Department of Fish and Game, the U.S. Bureau of Commercial Fisheries, and the University of California proposed an ecological experiment to assist the return of the Pacific sardine (Sardinops caeruleus) by imposing pressure on its chief natural competitor, the northern anchovy (Engraulis mordax) . Bitter controversy followed but in late 1965 the California Fish and Game Commission authorized a closely regulated anchovy reduction fishery. The controversy did not cease, but a modest fishery with a 75,000 ton quota was initiated.
Reduction landings during the 1965–66, 1966–67, and 1967–68 seasons were 16,800, 37,600 and 6,500 short tons, respectively. Landings were from an anchovy population conservatively estimated as between 4 and 5 million tons, 50% of which occurs off California, and consequently do not reflect a lack of abundance but low processor demand as dictated by declining world fishmeal prices. Landings were primarily by purse seiners operating in Monterey Bay and the inshore waters off southern California. Three-year-olds were dominant in central California landings and 2-year-olds in southern California. One-year-olds were most representative of the southern California live bait catch.
Both otoliths and scales from over 1,100 anchovies were used to compare two age-determination methods. The percent of agreement between individual age assignments was high and there were no significant differences in the resulting age compositions. Anchovy scales are caducous while otoliths are rarely unobtainable or deformed. Otoliths are therefore recommended for age determination of anchovies because they yield results comparable to scales and are more available.
During a 3-year period beginning in March 1966 nearly 381,000 anchovies were tagged and 1,080 were recovered on magnets installed in reduction plants. Recoveries demonstrate that anchovies can and do move considerable distances and between major fishing grounds in a short period of time. Anchovies from central California contribute to the southern California fishery and anchovies released off southern California were caught off central California and Ensenada, Baja California, Mexico.
A limited term live-bait sampling study determined that considerable manpower is required if the estimates are to be statistically significant. Since zero and 1-year-old fish are co-dominant in the live-bait fishery intensive sampling of this fishery may be useful for detecting changes in year-class strength and recruitment to the southern California commercial reduction fishery.