Lots of corals spawned on the night of Thursday 5th November (the night after full moon) at Big Vickis Reef at #LizardIsland. Photo: Lyle Vail.
Coral spawning is one of those natural wonders, a synchronized reproductive event that usually occurs at Lizard after November’s full moon. Fingers were crossed in the lead up this year, with the recent summer bleaching taking a massive toll on corals. We’re delighted to relay that on the 4th and 5th nights after the November full moon, researchers reported “a good one”, with sightings of widespread coral spawning at Big Vickis and Mermaid Cove. Nature is awesome.
The question on many of our supporters’ lips is how bad was this summer’s bleaching around Lizard? Now that eight or so months have passed since the warmest and most damaging months of February/March, the level of mortality is easier to gauge. Many of the shallow-water corals that had regrown over the past seven years, following the devastating 2016 bleaching, have died. These are mostly the faster-growing plate and staghorn corals. But those in water deeper than about 5 metres have not been affected as badly, unlike in 2016 when there was comprehensive death of corals at all depths. Other slower growing corals have shown more resilience, even in shallow water. The outer reef has not been impacted as significantly.
Media messaging has been confusing. Earlier in the year, reports of high coral cover contradicted reports of mass bleaching. Broadly speaking, this can be put down to time lags – when some of the reports came in (such as reports by the Australian Institute of Marine Science, AIMS) the corals were bleaching, though recorded as live coral cover. The full extent of bleaching – and mortality – along the GBR won’t be known until the more broadscale surveys are done. A summary of AIMS’ most recent Long-Term Monitoring Program survey results are available here.
Click here to learn more about coral spawning and other December 2024 news.
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