A new study released today by Bruno & Selig in PLoS Biology shows some very interesting trends in coral decline in the Indo-Pacific. In a nutshell:
- Average coral cover is lower than expected (22.1%, 2003).
- Coral cover is surprisingly uniform across regions.
- Coral cover on the GBR (often considered one of the best managed reefs in the world) is no higher than other regions (e.g. Phillipines).
- Although there is a lack of historical baselines, regional coral cover is at least 20% below historical records.
- Indo-pacific coral cover declined from 42.5% in the early 1980’s to 22.1% in 2003.
- This equates to an average rate of decline of 1% per year (approximately 1500km2 per year).
- Between 1995 – 2003 coral cover declined by 14% (3168km2 per year).
- In 2003, only 4% of surveyed reefs had high coral cover (>50%), and only 2% of reefs had very high cover (>60%).
- Regional scale decline of the Great Barrier Reef occured several decades earlier than often assumed (<1970).
- Coral decline in some sub-regions of the Indo-Pacific began during the 1960’s – 1970’s.
- Localised anthropogenic impacts have caused coral losses (e.g. sedimentation, destructive fishing practices).
Based upon 6001 surveys of 2667 reefs in the Indo-Pacific, the report makes for sobering reading. I have decided to add a “sub-section” to Climate Shifts entitled “Science Review” to encourage a weekly debate upon key scientific issues such as this – head over to Science Review to read more about the study and comment / debate the major findings.