A simulation study of crown of thorns starfish outbreaks on the great barrier reef

A spatial simulation of within-reef movement and activity of the crown-of-thorns starfish provides a tool with which to test hypotheses about the nature of outbreaks. Factors determining whether an outbreak destroys a reef or not include the initial number of starfish, their movement rates, and the degree of aggregation shown by the starfish. Behaviour of individual starfish may be less critical in determining the course of very large outbreaks compared with smaller outbreaks when a combination of reef shape and food limitation causes aggregation of starfish regardless of the degree of attraction between individuals.