Western Australia reefs hit by record coral bleaching

Western Australia has experienced its most widespread coral bleaching event on record, affecting approximately 2,000 kilometres of coastline. According to the ‘Status of Coral Reefs of the World 2025’ report, extreme heat stress persisted for between 80 and 160 days between August 2024 and June 2025.

In certain areas, water temperatures rose as much as four degrees Celsius above normal, leading to what researchers described as corals being ‘basically cooked’. The Pilbara reefs saw extreme bleaching and mortality rates exceeding 75 per cent. Additionally, the World Heritage-listed Ningaloo Reef recorded its most severe bleaching on record.

Dr. James Gilmour, a principal research scientist at the Australian Institute of Marine Science, noted that while some encrusting or circular corals may survive, they do not provide the same level of habitat for the reef as the species lost to the heat stress.