sardines, and is made more evident by normalizing the catch statistics and plotting
them over the same date scale (Alheit & Bakun, 2010, Fig. 17.20), and in both cases
the sardine pulses were simultaneous with dramatic dips in the associated anchovy
stocks. On the other hand, sardines were not strongly fished off Peru and Chile until
after the anchoveta collapse of the early 1970s, so the comparison does not go back
very far. Californian sardines did not follow the Japanese and Chilean stocks down in
the 1990s. Anchovy cycles are less similar. The northwest Pacific anchovy catches
only dropped by a quarter after 1970, not to near zero like those of anchoveta off
Peru. The shift in Asian anchovy landings could as well be explained by replacement
of anchovy in the marketplace by the newly accessible sardines. There is no question
that as sardines declined in both regions after 1990, anchovy stocks and catches
boomed in both. At a minimum, regime durations are similar in all three regions, and
they do involve a switch-off between the two wasp-waist fish species. Californian and
South African clupeid fisheries both have roughly the same periods as the Asian and
South American ones, but they are somewhat out of phase.
Fig. 17.20 Sardine (a) and anchovy (b) landing rates for the Japanese and Humboldt
Current fisheries standardized to percentage of maximum rates.
(After Alheit & Bakun 2010, based on data from Schwartzlose et al. 1999.)
A few of the hypotheses proposed in respect to regime control of “wasp-waist”
forage fish warrant review. While it is reasonable to postulate a role for fisheries in
the wasp-waist regime shifts, we also know that they occurred regularly in both