Settlement of white-spotted spinefoot, Siganus canaliculatus, was investigated in Okinawa island in 1988, by means of analyses of daily catches of adults with set nets, fish-lamp sampling at a fishing port and seine sampling in seagrass beds.
Analysis of daily catches in 1988 of set nets distributed around Okinawa island revealed a marked lunar periodicity in spawning of the spinefoot: schools of the spawners appeared in shore waters exclusively on neap tide days following a new moon in March through August. Size at settlement of juveniles was estimated between at 19.5 mm and 25.2 mm in total length. Settlement occurred on days around new moon in April through September mostly in seagrass beds. Estimated duration from spawning to the subsequent juvenile settlement became shorter with the advance of the season, being 28 days in April and 21 days in July and conversely correlated with water temperatures.