Study Shows Popular Fish Consumed in Hong Kong Under Serious Threat

A new study on the future of fish in the South China Sea reveals that key species consumed in Hong Kong are under serious threat from overfishing and habitat destruction, and unless immediate action is taken it will be too late.

Some of the topline findings of the study - Boom or Bust, The Future of Fish in the South China Sea - show that some marine resources have been fished down to as low as 5% compared to the 1950s, with others reduced to just 10% of their populations since the mid-1990s.

Even in more remote fishing locations, catch rates have declined 3 to 4 times over the past two decades.

Conducted by the University of British Columbia (UBC) Economic Research Unit and funded by Hong Kong-based ADM Capital Foundation and RS Group, the study offers a pathway to a more sustainable future.

“The study shows that to rebuild biomass of key groups to a healthy level, fishing efforts of all fishing fleets have to be substantially reduced,” said UBC’s Rashid Sumaila, principal investigator for the project.

Species under threat include the Napoleon Wrasse and the Coral Grouper, both highly prized in Hong Kong. Relative abundance of these two reef fish has declined by 80% in the past eight years alone.

While pollution and water quality is partly responsible, overfishing is the main culprit, and fishing methods play a key role in impacts on the environment.

“One of the findings of the study demonstrates that the way fish are caught is no longer sustainable,” said Doug Woodring, Co-Founder of Hong Kong's Ocean Recovery Alliance. “Not only are species being over-fished but the current fishing methods are destroying some coral reef habitats at a rate of 16% per decade. It is time to take action before it is too late.”

The study also contains projections through to 2045, with dire consequences for our future if action is not taken.

If nothing is done, by 2045, relative to 2015 fish stocks, all species studied will experience a decrease in biomass (quantity of fish in the ocean) ranging from 9 to 59% as a result of overfishing, ocean warming, ocean acidification and changes in primary productivity. We must urgently improve fisheries management and consider our impact on the ocean via CO2 emissions.

“The most vulnerable groups include grouper, large sharks, threadfin bream and large croaker, which are projected to drop by 50% or more during this period,” said UBC’s William Cheung, a co-author of the report.

The good news is that it is not too late to take action. The UBC scientists also conducted a best case scenario analysis under a sustainable management fishing regime with lowered global CO2 emissions. This indicates that efforts to improve fisheries management and reduce carbon emissions would have a positive impact on the wild population biomass of all species except crabs (due to their predators).

Either way, there are economic implications to these scenarios, both potentially with a loss of income and livelihood for fisherman, and an increase in the cost of fish to the consumer. If we engage in better resource management, however, there is a chance to modify practices and sustain stock levels, so that fisheries can still be productive for those who rely on them today.

“This study should be of interest to anybody who likes to eat seafood and cares about society,” said Yvonne Sadovy, a professor at Hong Kong University’s School of Biological Sciences. “Major urban centres like Hong Kong depend heavily on importing seafood, while hundreds of thousands of people in developing countries need wild fish for food and to support their families.”