A recent analysis explores the link between fish harvests and healthy coral environments. The research, conducted by the Woods Hole Oceanographic Institution (WHOI) and published in *Marine Resource Economics*, assessed the fish yields from nine fisheries that rely on the Great Barrier Reef in Australia during the years 2016 to 2020. The findings indicate that significant declines in fish yields could happen if efforts to restore coral reefs are not made a priority.
What are the implications of declining healthy coral reefs for fisheries? A recent study published in Marine Resource Economics, spearheaded by the Woods Hole Oceanographic Institution (WHOI), looks into the relationship between fish yields and live coral ecosystems. Researchers examined the yields from nine fisheries that depend on Australia’s Great Barrier Reef from 2016 to 2020. The results indicate that without prioritizing coral reef restoration, substantial losses in fish yields may be imminent.
In 2024, the Great Barrier Reef faced one of its most severe bleaching episodes ever recorded. An aerial survey by the Australian Marine Institute revealed that 73% of the checked reefs within the Great Barrier Marine Park showed signs of bleaching. These ecosystems depend heavily on tiny algae known as zooxanthellae, which play a crucial role in coral health and give it vibrant colors. Increased sea temperatures stress corals, leading them to expel these algae and consequently bleach. If the warming persists, these algae may fail to return, jeopardizing coral life. Over the last three decades, ocean warming has contributed to a 19% decline in the area covered by coral reefs worldwide.
“As coral rapidly declines, fish species that can survive without them will be forced to relocate. This will lead to dispersed populations, which can translate to lower yields for fisheries,” explained Marine (Yaqin) Liu, an environmental economist at WHOI. “Fish species that depend on reefs for nutrition or protection, like butterflyfish and coral trout, will see their numbers and consequently their yields shrink.”
The research highlights coral trout and saddletail snappers as the fisheries most at risk, as both depend on outer-shelf reefs for their habitats. According to the findings, if the live coral cover on the Great Barrier Reef decreases from 30% to 25%, the maximum sustainable yield for coral trout would decline by 8%, while saddletail snappers would experience a 19% drop. Furthermore, a reduction in live coral cover from 10% to 5% would result in a 27% decrease in yields for coral trout and a staggering 56% for saddletail snapper.
“Coral trout and saddletail snapper are significant to Queensland, Australia’s line fishery, an industry valued at $27-31 million,” noted Qingran Li, an assistant professor of economics and financial studies at Clarkson University in New York. “Although the methods used in this study don’t allow for straightforward financial predictions, it’s clear that a decline in fishing yields could substantially impact the economy, leading to job losses and decreased exports.”
As sea temperatures continue to rise, the likelihood of coral bleaching events will also increase. Coral reefs are home to 25% of marine species and serve as a shield for coastal communities against severe storms. They also contribute significantly to tourism and fisheries income annually.
“Backing claims about climate change with solid data is essential. Responsible fisheries are taking action to protect coral reefs by adopting sustainable practices, yet issues such as ocean warming and acidification pose additional threats to coral and fishery productivity,” Liu emphasized. “WHOI’s Reef Solutions Team remains focused on researching and developing innovative methods to restore and fortify coral reefs, aiming to apply successful strategies worldwide.”
