The Reef Authority’s November health update and AIMS’s biggest restoration trial yet land in the same week. Spawning-season trips are on — watch the heat into summer.
The Great Barrier Reef Marine Park Authority’s November 2026 reef health update is the baseline: sea surface temperatures rose about 1°C in October and are now above the long-term average in all regions. A strong El Niño is established and forecast to peak around November or December, then run into autumn 2027. Coral spawning is already underway on some inshore reefs; mass spawning is expected in late November.
October surveys logged 672 Reef Health Impact Surveys on 70 reefs. Low-level bleaching appeared on 10 of 40 Northern, 3 of 24 Central, and 4 of 6 Southern reefs surveyed. Coral disease was low to moderate on 17 of 70. Tourism operators in the Reef Protection Initiative culled 429 crown-of-thorns starfish in October. NOAA Coral Reef Watch’s four core GBR stations were still at No Stress on the 7 November station list.
AIMS has started this season’s Pilot Deployments Program. Its 5 November media release aims for up to 120,000 coral seeding devices around the Keppel Islands and off Cairns and Port Douglas; the AIMS project page cites around 150,000. Treat the figure as a range until AIMS reconciles it.
Late-November spawning can mean night dives timed to the full moon—book with operators who know local spawn nights. Expect warmer water than a typical spring. Give restoration crews space if you see seeding gear. Keep logging bleaching and COTS for Eye on the Reef if offered.