Coral reefs support a quarter of all marine life, feed hundreds of millions of people and contribute vastly to the global economy. But they are dying in mass bleaching events, as climate change warms our oceans and breaks down vital relationships between corals and energy-providing algae.
A new commentary, published in Communications Biology from Nature Research, provides hope that a shift in research focus towards coral immunity will support reef conservation and restoration efforts.
Dr Caroline Palmer, Visiting Research Fellow at the University of Plymouth, has spent more than a decade examining coral health from an immunological perspective.
In particular, she has identified coral immune mechanisms and sought to understand what enables some corals to survive while others die. This led Dr Palmer to discover that corals with higher immune defences are less likely to become diseased or to bleach.
In her latest work, she expands on this observation, drawing on a theory from insects that explains how corals might coexist with specific microorganisms, as a holobiont, while resisting infection or other disturbances.
Dr Palmer also presents a model of coral susceptibility, whereby investing in immunity enables coral, with its microorganisms, to tolerate more damage before initiating an immune response. This model describes how coral tolerance may vary among corals indicating their susceptibility to disturbances, such as bleaching events.