Potential geographic shifts in the coral reef ecosystem under climate change

• Published in: Progress in Oceanography
• Main Authors: Chaudhary, Chhaya, Alfaro-Lucas, Joan M, Simões, Marianna VP, Brandt, Angelika, Saeedi, Hanieh
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: Elsevier 2023
• Subjects: Arctic Ocean; Climate change
• Online Access: https://epic.awi.de/id/eprint/58986/; https://epic.awi.de/id/eprint/58986/1/1-s2.0-S0079661123000447-main.pdf; https://doi.org/10.1016/j.pocean.2023.103001; https://hdl.handle.net/10013/epic.0a5e83f9-d107-4478-8837-0a3c082c93b4

The coral reefs are the most diverse marine ecosystem in the world. Considering its contribution as a natural resource for humanity and global biodiversity, it is critical to understand its response to climatic change. To date, no global predictions have been made about potential ecosystem changes in relation to its inhabiting species. Predicting changes in species' climatic suitability under increasing temperature and comparing them among species would be the first step in understanding the geographic and taxonomic coherence and discrepancies that may occur within the ecosystem. Using 57 species-specific global climate suitability models (of corals, molluscs, fish, crustaceans, and polychaetes) under present and future climate scenarios (RCP 4.5 and 8.5), we compared the potential coherence and differences and their cumulative impact on the ecosystem in warm, cold, shallow, and deep waters. Under the climatic scenarios, nearly 90% of 30 warm-water species were predicted to lose their suitability in the parts of the Indo-west Pacific, the Coast of Northern Australia, the South China Sea, the Caribbean Sea, and the Gulf of Mexico, resulting in the overall southward shift in their distributions. In contrast, a mixed response occurred in 27 cold-water species, with most northern temperate/boreal ones increasing their suitability in the Arctic Ocean and the Arctic species declining overall. We noticed that irrespective of their taxonomic group, the species with wider distribution ranges (thermal and geographic) had larger predicted gains in their suitability than their stenothermal counterparts, suggesting an increase of generalist species and a decline of specialist (endemic) species of the ecosystem under a warming climate. Our coherent projections of species' climatic suitability in warm and cold habitats of the tropics, temperate, boreal, and the Arctic, represent significant taxonomic groups of the ecosystem. This might indicate mass extinction risk (local– in the tropics and northern temperate regions, and ...