The annual reproductive cycle of Oreaster reticulatus (L.) (Echinodermata: Asteroidea) and interpopulation differences in reproductive capacity

Annual reproductive and storage cycles of the asteroid Oreaster reticulatus (L.) were followed by organ index methods in populations from St. Croix in the U.S. Virgin Islands, and Carriacou and Union Island in the Grenadines. The periodicity of these cycles and their inverse relationship were similar among populations, but phase and amplitude varied. Gonad growth was activated in the spring (February to March) and progressed until spawning occurred in late summer or fall (July to October). The pyloric caeca increased in size during the quiescent phase of the gonad cycle (November to January), then decreased with increasing reproductive development to a minimum coincident with the spawning period. Reproductive development and spawning were more synchronous in the St. Croix populations than in those of the Grenadines. The inverse relationship between the storage and reproductive cycles indicated that gonadal development was subsidized by nutrient reserves previously accumulated in the pyloric caeca. Marked differences in storage and reproductive capacity among populations in the same geographic locality are attributed to differences in the quality and/or quantity of available food resources.