Microbial communities are the first to react to environmental changes and may in the future be used as potential indicators of environmental degradation and tipping points of ecological coral reef conditions. Our researchers have collaborated with researchers from James Cook University and Queensland University, Australia, and the Australian Institute of Marine Science, in a project promoted by the Australian National Environmental Science Program about the Great Barrier Reef microbial communities.

Coral reefs are under increasing anthropogenic pressure leading to the global degradation of these ecosystems. Several studies have shown that in addition to the global and devastating effect of rising seawater temperatures, local pressures such as overfishing, declining water quality and the appearance of coral predating crown-of-thorns starfish are driving declines in coral conditions globally, and in particular in the Australian Great Barrier Reef. In the recently published meta-analysis led by Pedro Frade, a CCMAR researcher, in collaboration with Australian researchers was studied one of the least well-understood communities: the bacterial plankton of the Great Barrier Reef waters and its role in the health of coral reefs.

Microorganisms are fundamental drivers of biogeochemical cycling in coral reef waters and to the health of all marine animals, but their contribution to the functioning and resilience of reefs is not well understood. In order to understand this functioning, researchers have analysed the composition of microbial communities in the surface waters of the Great Barrier Reef and identified groups of microorganisms characteristic of different types of reefs (e.g. coastal versus more oceanic reefs) and diagnoses of different conditions (e.g. along nutrient gradients).
The study shows that microbial communities in the surface waters of the Great Barrier Reef are strongly related to the predominant conditions around them (such as temperature). Pedro Frade, the first author of the study and CCMAR researcher, explains that " "this high degree of predictability in microbial communities and their involvement in coral health allows us, in the future, to use microbes as indicators that anticipate the deterioration (or recovery) of the health of the coral reef ecosystem". 

The establishment of a network of microbial observatories on the Great Barrier Reef will help monitor coral reefs, using microorganisms to determine threats to these ecosystems. Pedro Frade says that in the future this study "may lead to the establishment of a set of microbial tools that allow real-time monitoring of the health of coral reef ecosystems in the Great Barrier Reef and other parts of the world, contributing to the conservation of these marine ecosystems already seriously threatened by global climate change".

You can read the full article HERE.