Internal iron tags recovered by magnets demonstrate general movements of pilchards (Sardinops caerulea(Girard)) from Canadian to California fishing grounds. Consideration of recoveries in respect to tonnages of fish landed, size of fish landed, and efficiency of recovery show that in the first year after tagging, tagged fish are more concentrated on northern fishing grounds than on those of California. After the first year the reverse is true. Canadian tags during their first year are more concentrated on the fishing grounds off San Pedro than off central California. Later this condition is not observed. Fish of the 1939 year-class present in California waters in 1940 were taken by the Canadian fishery in 1941. The dates of recovery of first year tags on the United States coast indicate a rather orderly migration. Minimum estimate of the fastest rate of migration indicated gave 14.3 km. per day. In contrast to the inferred condition on major migrations, pilchard movements on northern fishing grounds are very confused. Definite movements from the Washington coast to the Canadian coast are demonstrated. Fish taken in the inlets of Vancouver island during the winter months are part of the general pilchard population. The total mortality rate of the large pilchards tagged in connection with Canadian fishing operations is about 71% per annum.