Fishing vessels have doubled since 1950, but catch has dropped by 80 percent
A recent study led by the University of Tasmania has revealed that the global fishing fleet grew from 1.7 million vessels in 1950 to 3.7 million in 2015. However, the total catch dropped by more than 80 percent in the same time frame.
According to study lead author Yannick Rousseau, the findings reflect growing pressure on marine resources and a fall in the abundance of fish.
“What we have seen over the last 65 years is more and more fishing vessels chasing fewer fish,” said Rousseau. “Since 1950, a dramatic increase in the size of the fishing fleet in Asia has more than offset small declines in North America and Western Europe.”
“Most of the increase in vessel numbers has been in motorized fishing boats, a change from the unpowered ‘artisanal’ fishing vessels that once characterized Asian and African fishing fleets. But, despite its advanced technology and increased numbers, the modern motorized fleet is having to work much harder to catch fewer fish.”
Rousseau explained that scientists use a measure of catch per unit of effort (CPUE) to evaluate fisheries management and the well-being of fish stocks.
“CPUE reflects how many fish are caught for the amount of effort expended, such as during a day’s fishing, and this measure paints a dark picture of the state of the ocean’s resources,” said Rousseau.
“In recent years, a sharp drop in CPUE in Southeast Asia, Latin America and the Southern Mediterranean indicates their fisheries expanded at a much faster rate than fish stocks could support.”
In developed countries such as Australia, the researchers found that CPUE has recently stabilized due to more effective fisheries management and a sharp fall in the size of the fishing fleet over the last decade.
“However, on current worldwide trends we can expect to see a further one-million vessels on the water by mid-century and the average engine power of the global fleet continues to increase,” said Rousseau. “These changes will further challenge the sustainable use of fisheries resources in coming years.”
“This is a particular concern for populations in regions such as Southeast Asia, where a high proportion of people rely on fish for sustenance. Our findings suggest that additional management measures are urgently warranted to ensure the future sustainability of global marine resources.”
The study is published in the journal Proceedings of the National Academy of Sciences.
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