Why Is Coral Bleaching a Problem and What Do We Have to Prepare for?
“Why is coral bleaching a problem, and why should I really care?” This is one of hundreds of similar questions that you can find online with people not fully understanding the extent of the destruction that the current bleaching events could lead to in the near and far future. As corals all around the world continue to be affected, scientists worry that, in many areas, coral reefs will no longer have enough time to recover before the next significant bleaching event occurs. If that happens, then corals affected by the severe bleaching events of the past three years – such as the coral formations in Southeast Asia and the Great Barrier Reef – could be in serious danger in the near future.
When Does Coral Bleaching Occur?
Coral bleaching happens when the algae that help sustain coral polyps with energy are expelled. This can happen as a result of triggers such as increased temperature, sedimentation, oxygen starvation, bacterial infections, sea level changes, disease, ocean acidification and the presence of various pollutants. Mass bleaching events have happened to an increasingly greater extent, as global warming shifted the water conditions that used to allow the symbiotic relationship between corals and zooxanthellae algae to flourish.
The Effect of Global Coral Bleaching Events
Global warming has led to many ecosystems being affected by heat waves that, in the case of the marine world, often translate into large, global scale El Nino events. One such event has taken out more than 16% of the global population of coral reefs in 1998, and recent events, albeit smaller, have still caused significant devastation. The past three years are a good example of that, as 2014 has seen the rise of the largest and most destructive coral bleaching event in history. The event has affected all the coral reef areas in the world, and the Great Barrier Reef took the brunt of it all. It is estimated that half the corals belonging to the Great Barrier Reef were killed and a large portion of the surviving ones were also affected, although to a lesser extent. A study conducted in the Maldives has shown that 60%-90% of the reefs were bleached, and all the reefs were affected at least slightly.
Catastrophic Long-Term Estimates about the Aftereffects of Bleaching
Estimates show that about 10% of the world’s coral reefs are already dead and up to 60% were affected by coral bleaching and destructive practices such as overfishing and pollution. Scientists believe that percentage will rapidly grow to 90% as activities like fishing and tourism continue to expand. By 2050 all of the world’s coral reefs might be in significant danger. As we can clearly see, the issue of “why is coral bleaching a problem?” may be a very current one, and not just a remote problem that we may have to address in the far away future.