Re-examination of the reef corals of Cocos (Keeling) Atoll, Charlie Veron

Ninety nine species of reef corals are recorded from Cocos (Keeling) Atoll in the eastern Indian Ocean. Of this all but twelve are known from Western Australia. Nine species have not previously recorded from the eastern Indian Ocean and threee (one being taxonomically doubtful) have not previously been recoded anywhere. Principal factors affecting the diversity of species are summarised: the effects of Acanthaster outbreaks, short and long-term changes to water circulation in the atoll lagoon, cyclones, and effectiveness of self-seeding. Surface circulation patterns controlling the origins of coral propagules from major reef areas are summarised as far as present knowledge allows. It is concluded that a minimum of 23 days would be neccessary for propagule transport from Indonesia in winter and twice that time in March, when the majority of reef corals spawn in Western Australia.