the spring swarming of caplin, when large numbers of these fish come inshore to spawn; also, the time when this swarming takes place.
1964  A few part-time fishermen, who put briefly to sea when the caplin arrive, and quit after three or four weeks, are spoken of contemptuously by the full-timers as "fishing only in the caplin scull."
1964  In vast numbers they stream past the headlands, into the bays, toward the sand and shingle beaches. This is the "caplin scull," the annual miracle which renews the Newfoundland fisheries and makes them the most productive in the world.