The yield of fisheries prosecuted by the major industrialised nations could be increased by 55 percent, according to Ray Hilborn, a professor in the University of Washington’s School of Aquatic and Fishery Sciences. He said 14 per centcould be achieved by rebuilding depleted stocks and 41 percent by fishing harder on under-exploited stocks.
Addressing delegates at the “New Challenges and Opportunities facing Marine Fisheries Science” conference at Fishmongers’ Hall in London on 31 October, Hilborn gave a very upbeat appraisal of the world’s fisheries in direct contrast to the usual messages of doom and gloom, particularly emanating from NGOs.
The main thrust of Hilborn’s contribution to the conference was to pick up on the point made by other speakers on how to feed an expanding world population that is predicted to exceed 9 billion people by 2050. (The conference was held on the actual day that the population was expected to hit the 7 billion mark.)
Hilborn said that there was a greater availability of fish for human consumption than was generally supposed and for a lot of fisheries yield could actually be increased. There had been a projection in 1998, based on the trophic level of landings, that all large fish used for direct human consumption would have disappeared by 2048.
However, a re-analysis of the data showed that the trophic level of catches was actually increasing. “We shall have nothing to eat but bluefin tuna,” said Hilborn.
Hilborn pointed out that the data used are restricted to the major industrialised fisheries of the developed world. “But, of course, that includes most of the capture fisheries that we, in the West, eat.” He also said the abundance of industrial fish stocks appears to be stable.
The world’s wild-capture fisheries had plateaued at about 90 million metric tons since the 1990s and, said Hilborn, many fisheries had been assessed as being fully exploited.
Many NGOs considered “fully exploited” fisheries to be in trouble so fishing effort should be scaled back, said Hilborn, but he disagreed with their views pointing out that we obtain food from fish stocks by fully exploiting them. “Fully exploited is where we want to be,” he said.
Hilborn had several messages for NGOs in his presentation, and listening to him one could be forgiven for thinking that all future food production should come from the sea rather than from the land if we want to “save the planet.”
He compared the environmental cost of fishing with the environmental cost of providing protein food by other means. The energy cost of fishing for small pelagic species — sardines, herring and mackerel — was the lowest for any form of food production, he said.
Hilborn showed a slide comparing how much water was needed to produce various types of animal protein — it takes 2 tons of water to produce 1 portion of beef, and 1 tons of water to produce 1 portion of chicken or pork — and pointed out that capture fisheries also don’t involve the use of fertilizer or antibiotics as does farming animals on land.
Furthermore, fishing involves less emissions of carbon dioxide than farming land for animal protein production. “If you’re worried about carbon dioxide then don’t eat meat,” Hilborn told the audience.
“Fisheries may have less biodiversity than organic agriculture,” he said, “because agriculture rips out native plants and replaces them with exotics. However, we would cut down more forests [to use the land for agriculture] if we stopped fishing as many NGOs want.”
Hilborn pointed out that the fastest form of food production is aquaculture, but said that work was also going on to rebuild wild fish stocks. “Europe is behind North America in rebuilding stocks, but it’s getting there. Cod stocks in the Barents Sea are the highest they’ve been for 70 years, and the WWF says it’s now OK to eat North Sea cod.”
It was a refreshing change to listen to such an upbeat message, and the global fisheries industry should make sure that it is heard. The media are full of tales of woe about how few fish are left in the sea, but many stocks are healthy and catches could be increased.
Presentations from the conference will soon be available on the Fishmongers’ Company’s website, www.fishhall.org.uk.
