Like many animals, the coral Astrangia poculata, which is found mainly in the shallow waters of the western Atlantic Ocean and the Caribbean Sea, as well as off the coast of western Africa, spends the winter in hibernation. This is the time when the microbiome present on it performs regeneration.
When coral Astrangia poculata falls into hibernation, the microbiome living on it (the totality of microorganisms found in it) mixes with each other, according to research conducted by scientists from the University of California, Davis. According to experts, this is how microbes, i.e. bacteria, fungi, viruses and archaea inhabiting this coral, regenerate and prepare for the next year.
This discovery could give us a better idea of how corals might respond to climate change. As waters around the world warm, protecting the coral microbiome will be critical. The latest study could provide experts with valuable insights into how best to keep these marine organisms fit and healthy.
“Hibernation, or sleep, is a response to an environmental stressor, in this case cold stress,” said ecologist Anya Brown of the University of California, Davis. “If we understand more about this recovery period, it may help us understand what microbes may be responsible for coral recovery in warmer tropical systems.” The study was published in Applied and Environmental Microbiology.
Study of microbes found on corals
Coral Astrangia poculata occurs in the waters of the western part of the Atlantic Ocean and in the Caribbean Sea. It can also be found off the west coast of Africa. When the water temperature drops, the coral falls into a deep sleep: it retracts its arms, stops eating, and ignores physical touch.
Between October 2020 and May 2021, Brown and her team collected 10 different coral colonies Astrangia poculata from a depth of about 18 meters off the coast of Massachusetts. They were divided into three categories representing specimens collected before, during and after hibernation.
Careful analysis in the microbiome lab of the collected specimens revealed that pathogen-associated microbes as well as nutrient-absorbing microbes are released during dormant periods. By contrast, microbes that can supply corals with nitrogen increase in number, suggesting that corals are effectively improving their microbiome community while maintaining some diversity.
This fits with the team’s hypothesis – that a “reset and restructuring” process is underway that protects the microbial community and meets the needs of the coral when it is both “awakened” and “dormant”.
“This study shows that microbes respond to stress and recover in a predictable pattern,” said marine microbial ecologist Amy Apprill of the Woods Hole Oceanographic Institution in Massachusetts. “This is fundamental knowledge that could help us develop probiotics or other microbes for stressed tropical corals.”
The experts’ next step is to better identify the microbes that help corals stay protected and recover. These could then be used or modified to maintain coral health.
According to the authors, the publication of this work opens up many research opportunities.
– You may ask yourself why corals wake up in early spring? This study suggests that key groups of microorganisms may play an important role in triggering the onset or emergence from dormancy of this coral and regulating its microbiome, noted Brown.
Science Alert, tvnmeteo.pl
Main photo source: Alicia Schickle, Roger Williams University