As the Great Barrier Reef continues to suffer from the devastating effects of climate change, researchers have discovered that certain types of friendly bacteria help corals remain healthy during times of stress, and could provide the key to preserving certain aquatic ecosystems in face of rising ocean temperatures.
According to a statement released by the Great Barrier Reef Foundation, scientists “have been able to prove for the first time, in a laboratory setting, that feeding corals beneficial probiotics increases their overall health and improves their chance of survival during heat stress.”
The discovery was made by an international team of researchers who treated numerous species of coral with certain types of beneficial microorganisms at the world’s largest artificial ocean, known as The Biosphere 2 in Arizona, and in Hawaii. “Time and time again the corals that had received the probiotics were in better health than those that had not,” said lead scientist Professor Raquel Peixoto.
In recent years, the Great Barrier Reef has suffered several mass bleaching events, including one in 2016 that wiped out nearly a third of all corals in the reef. Bleaching occurs when the ocean temperature rises, causing corals to expel the colorful algae that live inside them and which provide them with most of their energy.
As a result, reefs lose their rainbow hues and fade to white. While it’s still possible for bleached corals to recover, many die if they can’t regain their algal communities quickly enough.
Yet researchers are now hopeful that the use of beneficial bacteria could help to protect reefs from the stress of rising temperatures and stave off future mass bleaching events. At present, lab-reared coral has a low survival rate when it is transplanted onto natural reefs, and scientists want to see if those that are fed on certain microorganisms in the lab fare better once they are out in the ocean.
Commenting on this research, Great Barrier Reef Foundation managing director Anna Marsden said that “people may be surprised to find out that just like us, corals rely on a host of good bacteria to help keep them healthy and, just like us, the balance between good and bad bacteria is often disrupted in times of stress.”
Researchers are continuing to run experiments in order to determine which types of bacteria are most beneficial for different species of coral. Given that this year’s bleaching event was the first to affect the northern, central and southern regions of the Great Barrier Reef, solutions like this are needed more urgently than ever.
