Mangrove lagoons of the Great Barrier Reef support coral populations persisting under extreme environmental conditions

Researchers have identified two extreme mangrove lagoons on the Great Barrier Reef (GBR) that support taxonomically diverse coral populations thriving under conditions of low pH (<7.6), low oxygen (<1 mg l-1), and highly variable temperatures (>7°C). These environments, which mimic predicted seawater conditions for the coming century, act as hot-spots of resilience for corals, challenging current understanding of their stress tolerance mechanisms. The study found that coral cover in these lagoons was typically low but patchy, with established colonies present. Physiological plasticity and flexibility in Symbiodiniaceae taxa associations were crucial in supporting coral survival. The research highlights the ecosystem service value of mangrove lagoons for corals, spanning from refuge to stress preconditioning, and underscores the need to study such extreme environments to better understand coral resilience.

Camp, E., Edmondson, J., Doheny, A., Rumney, J., Grima, A., Huete, A., & Suggett, D. (2019). Mangrove lagoons of the Great Barrier Reef support coral populations persisting under extreme environmental conditions. Marine Ecology Progress Series, 625, 1–14. https://doi.org/10.3354/meps13073