Big and strong cyclones have the potential to damage coral reefs up to 1000km away from their paths, according to a new study by researchers at The University of Western Australia and the Australian Institute of Marine Science.
The research findings, published today in Global Change Biology, highlight that some cyclones can create extreme sea conditions which threaten the health of coral reefs located up to ten times further away than originally thought and that these cyclones regularly affect reefs in Australia and around the world.
Professor Ryan Lowe, from UWA’s Oceans Institute said the research team investigated the effect of Tropical Cyclone Lua on Scott Reef, an isolated coral reef system 300km off the north-west coast of Western Australia.
“Despite the intense winds produced by the cyclone remaining 500km away from the reef, extreme waves in excess of 10m reached Scott Reef and remained large as the storm stalled for three-and-a-half days,” Professor Lowe said.
Following the impact of the cyclone, Scott Reef lost half its population of robust Porites corals and virtually all its more fragile branching Acropora coral species.
Lead author Dr Marji Puotinen from the Australian Institute of Marine Science said predicting which reefs could have been damaged from past cyclones without considering both their size and strength would underestimate the frequency of damage to many coral reefs, which could lead to unfortunate decisions when attempting to prioritise conservation efforts.
“When deciding where on the Great Barrier Reef, for instance, to invest millions of dollars to repair or enhance reefs, you don’t want to select a location likely to be regularly battered by cyclone waves,” she said.
Professor Lowe said the ability to bring together expertise from UWA and the Australian Institute of Marine Science allowed the multidisciplinary research team to further understand the complex spatial damage patterns of Cyclone Lua.
“Our research highlights the importance of working across disciplines to forecast how ecosystems such as coral reefs are impacted by major disturbances such as tropical cyclones,” Professor Lowe said.
“The advanced tools we normally use to predict storm damage were developed to forecast hazards to coastal populations and infrastructure, however there are many opportunities to extend these tools to improve predictions of storm damage to ecosystems, which pose a major threat to tropical reef systems worldwide.”