Reef Report for Thursday, December 30, 2004
Good News Regarding Coral Bleaching and Global Warming? Letís Hope!
Recent research on coral bleaching may hold some small promise for coral reefs worldwide in the face of climbing ocean temperatures.
Research by Dr. Andrew C. Baker, a scientist at the Marine Program of the Wildlife Conservation Society, has turned up some very exciting facts, and an equal number of questions, both of which are signs of cutting edge research in coral reef ecology.
Baker, who studies reef ecology in locations throughout the world, has lately focused his research on coral bleaching. To understand this research letís backtrack a bit and focus on how corals make their living:
Corals make their living through a cozy relation ship with algae. These algae actually live inside the coral cells, and provide energy in the form of carbohydrates, in exchange for the protection provided by living inside the corals. This is a classic symbiotic relationship, where two different organisms live in close association with both species receiving benefit.
When corals are faced with extremely high ocean temperatures they can expel the algae they are hosting, which can lead to coral death and leave the reefs full of dead white-colored coral skeletons, hence the term "coral bleaching".
Dr. Bakerís recent research focused on the kind of algae living inside corals, and compared them in areas of the world that are more subject to extremely warm temperatures with those that are not. What he found that the strains of algae found in corals in areas stressed by warm temperatures are more heat tolerant then those found areas under less high temperature stress.
This research indicates what might actually be happening when corals expel the symbiotic algae they are hosting. Are these corals Ďevictingí algae that cannot do the job in higher temperatures, and looking for tenants (other strains of algae) that can handle the heat, or are the algae Ďchecking outí, in search of more favorable conditions? Only further research will answer this question.
This research suggests that perhaps coral bleaching is a way that corals make room for algae that are able to handle higher temperatures. If this is true itís good news, suggesting that coral might be able to at least temporarily adapt to the warmer ocean temperatures forecasted by most models of global warming. This might just give nations worldwide a chance to agree on ways to reduce the production of the gasses (Carbon Dioxide, Methane, and others) that cause this problem. We urge you to ask your political leaders just what they are doing, and to alter the way you live to reduce your contribution to this problem.
As far as coral bleaching locally, current weather patterns are protecting the Great Barrier Reef as the summer months approach. Forecasts indicate that trade winds and weather patterns are favoring the mixing of cooler, deeper ocean waters with warmer surface waters, as well as normal rainfall; both are a factor in keeping ocean temperatures down and protecting the reef. Letís hope these predictions hold up.
More on Global Warming and itís effects on Corals
Protecting Coral Reefs, how you can take part.
The weekly reef report is written by Joel Groberg of DiveTheReef.com,
who compiles them from the many conversations he has with dive staff in the area, as well as† many other local sources in the dive
Index of all reef reports.