Population outbreaks of the large coral-eating crown-of-thorns starfish Acanthaster planci have inflicted severe damage on coral reefs in the Indo-West Pacific over the last few decades. A. planci individuals have been considered to mostly occur at very low density (typical density < 1 individual per hectare); therefore, they normally have little effect on the abundance of reef corals. However, the presence of a very high density of A. planci individuals leads to very extensive destruction of coral communities. Many studies have evaluated potential factors for controlling population outbreaks of A. planci; the results of these studies suggest that food availability is predominantly related to larval survival. In the central Ryukyu Islands, southern Japan, outbreaks of A. planci have been reported from the end of the 1960s. Thereafter, most areas in the central Ryukyu Islands have either had chronic small-to-large A. planci outbreaks or have not had A. planci outbreaks since the 1970s. The factors responsible for this difference are not known. In this talk, we will discuss historical outbreaks of A. planci in the central Ryukyu Islands and examine factors that may be responsible for the historical differences in these outbreaks among areas in this region that have had chronic or no outbreaks.