Status of the Coral Reefs at the Cocos (Keeling) Islands

1968 (including research or study) no part may be reproduced by any process, re-used or redistributed for any commercial purpose or distributed to a third party for such purpose, without prior written permission from the Director of National Parks. Any permitted reproduction must acknowledge the source of any such material reproduced and include a copy of the original copyright and disclaimer. 1 The Cocos (Keeling) Islands are a remote coral reef atoll located in the eastern Indian Ocean. The marine community comprises largely Indo-West Pacifi c species, with little endemism. A range of disturbances have impacted on the Cocos marine community including subsistence fi shing, cyclones, coral bleaching, crown-of-thorns starfi sh outbreaks, and mass die-off events. Disturbances such as these on remote islands have the potential to cause drastic changes in the marine community. To determine the status of coral reefs at Cocos and document changes in community composition and species abundances, Parks Australia has developed an extensive monitoring program using internationally recognised Reefcheck survey methods. Underwater censuses were conducted by Parks staff at 11 representative sites from 1997 to 2005. Data were collected on important indicator, keystone and harvested marine fi sh and invertebrate species as well as on habitat composition. Evidence from the underwater surveys at 11 sites from 1997 to 2005 indicates that the coral reef community at Cocos (Keeling) Islands is very healthy and in a stable period with little impact from anthropogenic activities. Live coral cover is high and there is minimal impact from coral damage, bleaching, and disease although some coral cancers are present. Crown-of-thorns starfi sh were found at high densities at some sites and further monitoring is required to determine the impact of these starfi sh on the coral community. Overall, fi sh and invertebrate abundances were found to be relatively constant throughout the survey period at all sites. A small number of signifi cant changes occurred in the abundance of some study taxa, but these changes Executive Summary were usually the exception, involving only short-term fl uctuations. Densities of fi sh and invertebrates calculated in this study were comparable with previous studies at Cocos (Keeling) Islands and similar to other coral reef locations. Two notable exceptions were the very high densities of small sea cucumbers and relatively low densities of snappers. Further monitoring will determine whether these levels are typical for Cocos (Keeling) Islands or just short-term phenomena observed during the …