Scientific study shows resilience among fragile coral reefs

Damaged coral reefs show the effects of a changing climate, but scientists have found coral reefs in the Pacific that are healthy and thriving far from human activity.

REUTERS/David Gray/Files
Snorkler inspecting the "Coral Gardens" located in Australia (June 11, 2015). Coral reefs have suffered under climate change, but scientists have found new reefs that may survive the change.

Coral reefs have been in decline for decades, but researchers have found evidence that some Pacific reef communities are thriving.

Scientists conducting a 10-year, 56-island survey on coral reefs have found isolated reefs that appear to be surviving the environmental stressors which have been damaging most others, showing signs of resilience and even recovery.

The long-term health of coral reefs has been a focus and concern of researchers for years. Previous studies found that coral growth rates decreased 40 percent over the past three decades. More recent studies offer that the dire predictions for the global health of coral reefs have now come to pass.

But what are scientists seeing that is offering hope against this downward spiral of coral reefs?

"Going to these uninhabited locations, you can still find reefs that look the way they did 1,000 years ago," said Jennifer Smith, ecologist and the lead author of the 10-year study, to The Washington Post

Ms. Smith’s team set out to study how coral reefs were affected by climate change and the intensity of the 1998 El Nino weather patterns, which damaged many coral reefs. The study was published in the scientific journal Proceedings of the Royal Society B in March.

Much of the study’s findings confirmed the grim reality found by other marine biologists: coral reefs were subject to mass bleaching (a process where a stressed reef expels symbiotic algae), contained less diverse fish life, and were overall less "healthy."

But Smith's team also found isolated reefs that appeared to be recovering. Reefs that are growing off of uninhabited islands and sheltered from the added stress of human-driven problems, such as overfishing, showed healthy levels of coral and algae growth.

"These results suggest that, in the absence of local human impacts, reefs may be more resistant or resilient to global change and provide incentive for local management action on more populated islands," the study states.

The nature of the study does temper the good news. Because the research was collected over a 10-year time frame, some of the sites that showed signs of recovery during early observation lack more current data. It is unknown if the recovery continued since, especially as climate change and ocean acidification have worsened over the years. 

But the study's possible solution, allowing coral reefs to recover by isolating them further from humans, could complement other options being developed by scientists.

Scientists have developed a possible treatment for decaying reefs that could promote growth, The Christian Science Monitor reported in February. The treatment acts as an antacid against the growing threat of ocean acidification and could potentially be used to stimulate growth in small, isolated reefs.

Research labs have also developed "super coral," the Monitor reported in November 2015, by introducing environmental and man-driven stressors gradually to normal coral with the hopes that the coral reefs would be better able to adapt and build resilience. The coral exposed to "(human)-assisted evolution" is then transplanted into other ocean reef communities.

While these new approaches show some potential to help mitigate or even reverse the damage done to coral reefs, it’s unclear if they will have lasting effects or could be implemented on a large scale.

"The question is not can they do it, it’s can they do it fast enough?" marine biologist Tom Oliver told The Associated Press.

of 5 stories this month > Get unlimited stories
You've read 5 of 5 free stories

Only $1 for your first month.

Get unlimited Monitor journalism.