Factors affecting recruitment variability of capelin (Mallotus villosus ) in the Northwest Atlantic

Year-class formation in beach-spawning stocks of capelin (Mallotus villosus ) in eastern Newfoundland is strongly influenced by the frequency of large-scale wind-forcing events that regulate the timing and frequency of larval drift. Recent analysis of capelin age-composition data revealed that the strong year classes in the beach-spawning stocks also occurred in a discrete, offshore stock of capelin on the Southeast Shoal of the Grand Bank some 350 km from the nearest spawning beach where capelin spawn annually during June/July at water depths averaging 50 m. The hypothesis tested from the observations described in this paper is that essentially the same kinds of environmental factors, operating during the immediate post-hatching period, are responsible for strong year classes in both stocks.