Acanthaster planci (L.) and Nardoa novaecaladoniae (Perrier, 1875) are two coral reef asteroids having planktotrophic and lecithotrophic larval development, respectively. Comparative sizes at metamorphosis are 0.5 to 0.7 mm for A. planci and 1.2 to 1.6 mm for N. novaecaladonine. Mortality rates of small juveniles (one month old) of each species were measured experimentally in the field on the Great Barrier Reef, Australia. Mortality rates of N. novaecaladoniae were low (1.5 %.d(-1)) compared to 7.8 %.d(-1) for A. planci. Survival of the two species was similar between habitats. However, mortality rates of A. planci were highly variable both within-sites and between-sites within-habitats (fore reef 15 m depth, reef flat 2 m and back reef lagoon 12 m). There was no apparent effect of density of A. planci on mortality rates. Mortality is thought to be principally due to predation by infauna which are abundant in the coral reef rubble. A study of survival rates of newly metamorphosed Nardoa sp. (1.0 to 1.2 mm) in Okinawa, Japan, found very low mortality rates of just 0.2 %.d(-1). The abundance of potential predators among the rubble infauna was very low on the Okinawan reef compared to the Great Barrier Reef. These studies provide evidence of the importance of predation as a determinant of survival rates of small starfish and that a reproductive strategy providing for a large size at settlement facilitates greater survivorship.