Poster Australian Marine Sciences Association 2022

Planting ‘nuggets of hope’: utilising coral fusion to establish heat-evolved symbiont populations in coral reefs (#488)

Bede Johnston 1 , Matthew Nitschke 1 , Wing Yan Chan 1 , Madeleine van Oppen 1
  1. Australian Institute of Marine Science, West End, QUEENSLAND, Australia

Due to the unprecedented rate of anthropogenic climate change, it is unlikely that the spread of existing adaptive alleles or new adaptive genetic mutations in the coral holobiont will occur fast enough to ensure the survival of coral reefs as they are known today.  The use of assisted evolution strategies that can accelerate the adaptive responses of the coral holobiont to climate warming are viewed as increasingly necessary. One such strategy (i.e., experimental evolution) focusing on the photosynthetic algal symbionts (Symbiodiniaceae) has led to the generation of laboratory-evolved strains with enhanced thermal tolerance. Following the re-introduction of heat-evolved symbiont strains into coral larvae, juveniles and adults, some strains can increase the thermal tolerance of the coral holobiont in the laboratory. This project will expand on this early work and investigate the potential of coral tissue fusion as a tool to introduce populations of these heat-evolved symbionts into coral reef communities. Coral micro-fragments dominated by heat-evolved symbionts will be generated and fused to in situ reef colonies of the same species in an attempt to exchange and permanently establish populations of heat-evolved algal symbionts thereby providing ‘nuggets of hope’ for future coral reef thermal bleaching resilience.