Science Times reported on April that the Great Barrier Reef underwent its third major bleaching event in the last five years. The reef has experienced a back-to-back coral bleaching in 2016 and 2017 that killed almost half the reef's corals.
But bleaching does not necessarily mean that it is already dead, according to Terry Hughes director of the ARC Centre of Excellence for Coral Reef Studies at James Cook University. This only means that the coral needs help for it to recover.
Now, the scientists believe that probiotics similar to those found in yoghurt can boost the health of the corals to help it withstand the heat stress.
Australia's Great Barrier Reef has suffered its third coral bleaching event in the last five years during March 2020 https://t.co/NcZQwC8ahn pic.twitter.com/RE5iaSl84r — Reuters (@Reuters) June 4, 2020
Breakthrough: Feeding Corals With Probiotic Enriched Plankton
An international team made the breakthrough of using probiotics to help the Great Barrier Reef soon after it weathered on its third major bleaching in five years.
Probiotics have been widely regarded as a success in improving human and animal health, but this will be the first time that it will be used in marine ecosystems, according to The Courier.
Just like humans, corals rely on good bacteria to help keep them healthy, said Anna Marsden Managing Director of the Great Barrier Reef Foundation. "And, just like us, the balance between good and bad bacteria is often disrupted in times of stress," she added.
Corals are more prone to infections and less likely to survive if they are exposed to stress-triggered imbalances.
The scientists experimented with the corals by injecting probiotics into them but then decided to feed them instead of their zooplankton prey enriched with probiotic. The plankton absorbs the good bacteria through the water, and the coral then feeds on the plankton. It is like feeding them yoghurt full of good bacteria.
Their experiment resulted in corals surviving to stressful times, protecting them from being bleached.
Coral Reef Restoration
The researchers hope that their technology can be used to improve the health of artificially-reared corals that are used in reef restoration projects which have a low rate of survival when introduced to the natural environment of the reefs.
They are planning to use it within a year, 7news reports.
Lead author, Professor Raquel Peixoto of the Federal University of Rio de Janeiro is currently testing which groups of good bacteria are the best for each coral species. At the same time, their team is also investigating ways to increase the technology's application.
They are thinking to do this by delivering parcels of slow-release probiotics to targeted reefs in times of heat stress which causes the bleaching of the coral reefs.
Probiotics in Aquaculture
Probiotics are also good for marine life to accelerate their development and increase their chances of surviving until adulthood. Their use in aquaculture has now extended to improving fish growth and reproduction from initially being used for disease control.
According to Global Engage, probiotics function as nutrient sources providing enzymes for better digestion, modulating the immune system and increasing the immune response against pathogens. The most common probiotics used in aquaculture are the Lactobacillus-sp., Bacillus-sp., Enterococcus-sp., and yeast, Saccharomyces cerevisiae.
They are feed to the organism to modify the gut microflora and replace the harmful bacteria with the good ones. Their proliferation inside the organism's gut increases digestive enzymes leading to improved digestive processes and nutrient utilization.