A new study of the Great Barrier Reef has revealed that the network of no-take marine reserves supplies nearly half of the region's coral trout fishery catch.
The research, led by Professor Michael Bode from the QUT School of Mathematical Sciences and published in Science Advances, revealed that despite covering only 30 per cent of the reef's habitat, these protected areas account for 47 per cent of the coral trout catch in fishing areas and contribute 55 per cent of the species' reproduction.
The Great Barrier Reef is protected by a network of marine reserves designed to conserve its biodiversity. These reserves protect critical habitats for many species, including the coral trout, the reef's most valuable commercial fish.
"The marine reserve network on the Great Barrier Reef is not just a tool for conservation; it's a vital contributor to the sustainability of local fisheries and local jobs," Professor Bode said.
"By protecting fish populations within these no-take zones, we not only safeguard biodiversity but also guarantee that there will be a new generation of fish on the reefs that are open to fishing. This is a clear example of how protected areas can also benefit local communities and the economy, as well as the reef's unique biodiversity."
The study, conducted by a team including researchers from James Cook University and the Australian Institute of Marine Science, used decades of fish surveys, advanced oceanographic models, and high-resolution reef mapping.
Importantly, the findings show that despite marine reserves reducing the area available for commercial fishing, the network has a positive, amplifying effect on fishery yields. On many reefs, the density of fish in reserves is two to three times higher than on fished reefs, resulting in a higher reproductive output and a more sustainable fishery.
The study also highlights how all the reefs in the system benefit from the marine reserves, through higher larval supply.
However, across the Great Barrier Reef, nearly 95 per cent of reefs receive at least 30 per cent of their larvae from reserves, and 93 per cent of fished reefs benefit from at least 30 per cent of their catch originating from protected areas.
"This study reinforces the idea that well-managed marine reserves can be a win-win for both conservation and the fishing industry," Professor Bode said.
"The results provide clear guidance for future marine management efforts, showing that these reserves contribute significantly to sustainable fishery yields, as well as to the resilience of coral reef ecosystems."
Read the full study, Marine reserves contribute half of the larval supply to a coral reef fishery, published in Science Advances online.