Reef Health Update: Warm Waters, Localised Bleaching and a Busy Breeding Season

Sea surface temperatures across the Great Barrier Reef Marine Park rose slightly during the past week, particularly in Far Northern areas, as reduced cloud cover led to warmer conditions.

Despite the increase, experts say accumulated heat stress across most of the Marine Park remains below levels likely to cause widespread coral bleaching. Sea surface temperatures are currently sitting between 0.8 and 1.2 degrees above long-term monthly averages.

Forecasts suggest warmer-than-average conditions are likely to persist in the Far Northern region through March, while other regions are expected to remain within manageable limits. A gradual easing of warm conditions is anticipated from April.

The Bureau of Meteorology is forecasting a broad low-pressure trough to influence the region in the coming week, bringing increased rainfall, particularly to the Cape York and Wet Tropics catchments. Rainfall during the past reporting period was average or below average across most catchments, though heavier falls were recorded in the Burnett–Mary region, where some areas received more than 100 millimetres in a single day.

Monitoring teams completed 105 Reef Health Impact Surveys across 18 reefs in the Northern, Central and Southern regions over the past week. Low to medium levels of coral bleaching — between one and 30 per cent — were recorded on seven reefs. Additional observations through the Eye on the Reef program noted bleaching on 16 of 32 surveyed reefs. No fully bleached or recently dead coral was observed, with impacts remaining localised.

A rare sighting of a flatback turtle off Cape Tribulation has also highlighted the Reef’s busy summer breeding season. Turtle hatchlings are emerging from nests, seabirds are nesting across islands, and many fish species are spawning during this highly productive period.

Meanwhile, crown-of-thorns starfish control efforts continue across targeted reefs, with specialist dive teams surveying and culling the coral-eating starfish.

Marine monitoring teams are currently working at 34 sites across more than 1,000 kilometres of coastline, with ongoing water quality testing helping scientists understand how recent weather conditions are affecting nearby reefs.

Authorities say management efforts remain focused on supporting reef resilience through active monitoring, compliance enforcement and responsible use of the Marine Park.

PIC: Great Barrier Reef Heart Reef Whitsundays Stock Photo 1597510444 | Shutterstock

CAPTION: The Reef Authority continues to work closely with official organisations to provide accurate reports on the health of one of the country’s most treasured gems. Photo source: Shutterstock

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