A changing climate for coral reef management and adaptive restoration
Line K Bay.
Despite significant protection and management, the Great Barrier Reef (GBR) is in long term decline. The World Heritage listed ecosystem is under threat from a number of disturbances – most recently mass coral bleaching and mortality. The scale and intensity of mortality is increasing and is eroding the Reef’s resilience. To avoid ecological collapse or extinction, it is now clear that corals need to rapidly adapt, if reefs are to persist under current trajectories of environmental change. New management tools to facilitate and promote coral adaptation are in the feasibility stage and may have significant benefits for reef ecosystems under climate change. In this talk I will outline what we know about the adaptation potential of GBR corals and discuss – if and how – adaptation can be harnessed through adaptive restoration management interventions. I will give examples of research to link corals’ bleaching phenotype and genotype to develop and the genetic markers of heat tolerance. I will then examine ways in which adaptation can be enhanced through genetic interventions such as planned translocation of warm-adapted adults or through larval and juvenile seeding from ex situ selective breeding programs. Our models suggest that the natural spread of adaptive variants on the GBR may be too slow to keep pace with ecosystem change and that active interventions to increase the heat tolerance in local populations may substantially increase the pace of adaptation. I finish by considering the challenges facing coral reef managers to incorporate genetics and adaptation into conservation frameworks. This discussion will be framed not only in the context of regulatory and Research and Development knowledge gaps but will also comment on the social and economic barriers to implementation. I argue that the benefits and risks of any new interventions should be considered in addition to conventional management and supported by strong mitigation of CO2 emissions.