Research on the Great Barrier Reef has found severe coral loss to be associated with substantial increases in the size of large, long-living herbivorous fish. However, decreased recycling of this fish biomass could leave the ecosystem vulnerable to crashing. The research is published in the British Ecological Society journal Functional Ecology.
By comparing reef surveys from 2003-2004 and 2018, an international team of researchers led by James Cook University, found severe coral loss, of up to 83% in some areas, was associated with increases in fish biomass, productivity and consumed biomass, meaning the reef now has more energy stored in the form of fish weight, is able produce more fish weight and these fish are being consumed by predators.
Renato Morais, lead author of the study, said “It’s as if the herbivorous fish community has been scaled up, with larger fish growing and providing more food for predators when they die. However, this does not come without a cost”
Superficially, the increased biomass may seem positive from a human perspective, with the presence of bigger fish after a coral reef collapse suggesting a stable population. However, the researchers warn that reduced turnover, or recycling of biomass, in the reef could mean that this trend benefiting large fish might not last long.
Read more at British Ecological Society
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