The Wildlife Conservation Society today released initial field observations(野外观测,实地观察) that indicate that a dramatic rise in the surface temperature in Indonesian waters has resulted in a large-scale bleaching1 event that has devastated2 coral populations. WCS's Indonesia Program "Rapid Response Unit" of marine3 biologists was dispatched(调度,派遣) to investigate coral bleaching reported in May in Aceh–a province of Indonesia–located on the northern tip of the island of Sumatra. The initial survey carried out by the team revealed that over 60 percent of corals were bleached4.
"Bleaching"– a whitening of corals that occurs when algae5(海藻) living within coral tissues are expelled(开除,驱逐) – is an indication of stress caused by environmental triggers such as sea surface temperature fluctuations6(温度波动,温度涨落) . Depending on many factors, bleached coral may recover over time or die.
Subsequent monitoring conducted by marine ecologists from WCS, James Cook University (Australia), and Syiah Kuala University (Indonesia) were completed in early August and revealed one of the most rapid and severe coral mortality events ever recorded. The scientists found that 80 percent of some species have died since the initial assessment7 and more colonies are expected to die within the next few months.
The event is the result of a rise in sea surface temperatures in the Andaman Sea – an area that includes the coasts of Myanmar, Thailand, the Andaman and Nicobar Island, and northwestern Indonesia. According to the National Oceanic and Atmospheric8 Administration's Coral Hotspots website, temperatures in the region peaked in late May of 2010, when the temperature reached 34 degrees Celsius9—4 degrees Celsius higher than long term averages for the area.
"It's a disappointing development particularly in light of(根据,鉴于) the fact that these same corals proved resilient(有弹力的) to other disruptions to this ecosystem10, including the Indian Ocean Tsunami11 of 2004," said WCS Indonesia Marine Program Director Dr. Stuart Campbell.
WCS and JCU have been working in the region since March 2005. Surveys conducted in the wake of the Indian Ocean Tsunami in 2004 revealed that the many reefs of Aceh were largely unaffected by this massive disturbance13. Indeed, reefs severely14 damaged by poor land use and destructive fishing prior to the tsunami had recovered dramatically in the intervening years due to improved management. Government and community-managed areas in the region have been remarkably15 successful at maintaining fish biomass despite ongoing16 access to the reefs. But the bleaching and mortality in 2010 have rapidly reversed this recovery and will have a profound effect on reef fisheries(渔业,渔场) .
Of particular concern is the scale of the sea surface temperature anomaly(异常,不规则) which the NOAA website indicates has affected12 the entire Andaman Sea and beyond. Similar mass bleaching events in 2010 have now been recorded in Sri Lanka, Thailand, Malaysia and many parts of Indonesia.
"If a similar degree of mortality is apparent at other sites in the Andaman Sea this will be the worst bleaching event ever recorded in the region," according to Dr. Andrew Baird of the ARC Centre of Excellence17 for Coral Reef Studies at JCU. "The destruction of these upstream reefs means recovery is likely to take much longer than before".
"This is a tragedy not only for some of the world's most biodiverse coral reefs, but also for people in the region, many of whom are extremely impoverished18(穷困的) and depend on these reefs for their food and livelihoods19(生计,生活) ," said WCS Marine Program Director Dr. Caleb McClennen. "Immediate20 and intensive management will be required to try and help these reefs, their fisheries and the entire ecosystem recover and adapt. However, coral reefs cannot be protected from the warming ocean temperatures brought on by a changing climate by local actions alone. This is another unfortunate reminder21 that international efforts to curb22 the causes and effects of climate change must be made if these sensitive ecosystems23 and the vulnerable human communities around the world that depend on them are to adapt and endure."