(^) Similar sequences have affected sardine (Sardinops melanostictus) and anchovy
(Engraulis japonicus) fisheries off Japan (Fig. 17.18b), off western South America (S.
sagax, E. ringens) (Fig. 17.18c) and off southwest Africa (Namibia). All of these
regions show similar fishery regime shifts. In most of them changes in stock size are
accompanied by shifts in geographical distribution. That is well illustrated by the
Japanese sardine, which has a much smaller spawning range than feeding range
(Schwartzlose et al. 1999). Spawning is inshore around southern Japan and central
China, a range in which the stock mostly remains to feed when numbers are low. In
those times, the catch is mostly confined to the southern Sea of Japan and inshore
South China Sea. When the stock is large, however, it expands for feeding into the
northern Sea of Japan and eastward into the Pacific, sometimes sustaining fishing east
of the dateline. Both the California and Chilean sardines also show range expansions
when abundant and contractions when stocks are reduced (e.g. Bakun et al. 2010; Fig.
17.19).
Fig. 17.19 Distributional patterns of California sardines (Sardinops sagax caeruleus)
when more (right) and less (left) abundant.
(^) (After Bakun et al. 2010.)
(^) Regime shifts off Asia, California, and South America show some degree of
simultaneity. That was first commented upon by Kawasaki (1983), based mostly on
the sardine changes. Common timing is most evident for the Japanese and Chilean
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