A spectacular underwater phenomenon is unfolding across the Great Barrier Reef as reef fish gather in mass aggregations - some performing "dance rituals" - for a synchronised annual mass spawning event.
Thousands of reef fish species including coral trout, emperor, cod, surgeonfish and Spanish mackerel converge on key sites, synchronising their release of eggs and sperm into the water column.
Similar to coral spawning, fish spawning is dependent on lunar and water temperature cues - timed with the new moon, tides, sunset and water temperatures of 26 to 28 degrees - typically between October and December.
Reef Authority Chief Scientist Roger Beeden said the predictable mass aggregations of fish spawning is one of nature's most extraordinary displays - and one of the most critical times for protection.
"It's an incredible underwater spectacle - a synchronised dance of life that showcases the Reef's regeneration," Dr Beeden said.
- "Protecting these spawning events is crucial. These closures make a big difference in sustaining fish stocks, supporting tourism, and preserving livelihoods that depend on the Reef."
The annual event fuels the Reef's renewal, creating a burst of life that sustains everything from coral and clams to mackerel and turtles.
"Every spring the Reef comes alive with this breathtaking underwater ballet," Dr Beeden said.
- "It's a powerful reminder of the Reef's resilience and the importance of safeguarding these natural cycles so future generations can witness them too."
To give these spawning fish the best chance to reproduce the Department of Primary Industries, Fisheries Queensland implements a range of management measures to support this critical period.
Two coral reef fin fish closed seasons in east coast waters north of 24o 50'S (near Bundaberg) will be in effect from 18 to 22 October 2025 and 17 to 21 November 2025 inclusive.
Two Spanish mackerel closed seasons will be in effect in east coast waters north of 22o South (Near Stanage Bay) from 18 October to 8 November 2025 and 17 November to 8 December 2025 inclusive.
- "We know these science-based closures protect reef fish when they're most vulnerable - when they gather in large, predictable numbers to breed," Dr Beeden said.
"By allowing fish to spawn undisturbed, we're helping sustain healthy stocks and support livelihoods that depend on the Reef."
The Spanish mackerel closure also coincides with the species' breeding season - a period when these prized pelagic fish form dense spawning schools along reefs north of Townsville, making them particularly susceptible to overfishing.
Fisheries Queensland is responsible for managing the closed seasons for coral reef fin fish and Spanish mackerel.
Fisheries Queensland Executive Director Eddie Jebreen said fishing closures and no-take periods were in place to ensure the long-term sustainability of Queensland's fisheries and waterways.
"We'd like to thank all Queensland anglers who do the right thing and follow the rules, and help us spread the word of these closures," Mr Jebreen said,
"If we give these popular reef fish species a break for a few short days during spawning season, it can really help ensure fish stocks are sustainable for future generations."
