FACT SHEETS -
CORAL REEF IMPACTS
23 CROWN OF THORNS STARFISH
• Crown of starfish also known as COTS, are one of the few animals that actually eat living coral.
• COTS are named for the dense covering of thick sharp spines that look like thorns covering them. COTS have poisonous spines and are very painful if brought into contact with human skin.
• At low densities COTS are seen as a ‘normal’ part of the reef ecosystem. However outbreaks can occur where the number of COTS exceeds a critical amount potentially causing a major disturbance to the whole reef ecosystem.
• The Great Barrier Reef has been suffering from mass outbreaks for over forty years. While COTS outbreaks can dramatically decrease coral cover, coral reefs can and do recover from these outbreaks. This will depend on the coral reefs resilience however, which will be adversely affected by other man-made impacts, such as global warming.
• It has been suggested that human factors have contributed to the recent outbreaks of COTS on the Great Barrier Reef; however this has not yet been proved.
• Reef Check Australia identify and monitor COTS in their surveys. The information provided by Reef Check surveys will increase our knowledge about the extent and frequency of COTS outbreak.
• The Australian Institute of Marine Science (Crown of Thorns Questions and Answers): http://www.aims.gov.au/pages/reflib/cot-starfish/pages/cot-000.html
• CRC Reef (Crown of thorns): http://www.reef.crc.org.au/publications/newsletter/june04_cots.htm
• Wikipedia: http://en.wikipedia.org/wiki/Crown-of-thorns_starfish