Global fish catches are falling three times faster than official UN figures suggest, according to a landmark new study, with overfishing to blame.
Seafood is the critical source of protein for more than 2.5 billion people, but over-exploitation is cutting the catch by more than 1m tonnes a year.
The official catch data, provided by nations to the UN’s Food and Agriculture Organization (FAO), rarely includes small-scale, sport or illegal fishing and does not count fish discarded at sea. To provide a better estimate, more than 400 researchers around the world spent a decade finding other data to fill in the gaps.
The results, published in the journal Nature Communications, show the annual catches between 1950 and 2010 were much bigger than thought, but that the decline after the peak year of 1996 was much faster than official figures.
The FAO data indicated a catch of 86m tonnes in 1996, then a decline of 0.4m tonnes per year. In contrast, the new research estimates the peak catch was 130m tonnes, but declined at 1.2m tonnes per year afterwards.
“Our results differ very strongly from those of the FAO,” said Prof Daniel Pauly, at the University of British Columbia in Canada and who led the work. “Our results indicate that the decline is very strong and is not due to countries fishing less. It is due to countries having fished too much and having exhausted one fishery after another.”
Estimating subsistence, small-scale and illegal fishing is difficult, but Pauly said his team was confident in its results which - unlike the FAO data - includes estimates of the uncertainty. “This research is not based on a few studies here and there and then extrapolation,” he said. “It is based on the results of 200 studies we have conducted for about a decade by a network of 400 people in all countries of the world.”
The researchers used many different approaches to fill in the missing data, from hotel invoices for locally bought fish in the Bahamas to information on local fish consumption. (The Guardian)
PHOTO: Global fish catches rose from the 1950s to 1996 as fishing fleets expanded and discovered new fish stocks to exploit.
CREDIT: Eyal Warshavsky/Corbis.