AS BUSHMEAT becomes more scarce, with many species at risk of extinction, billions of the world’s poor are relying ever more on fish. Now the fish too could be doomed – by climate change.
Fish are the largest source of wild protein left on the planet. For about 2.6 billion people, some 40 per cent of the planet’s population, fish makes up a fifth of their protein intake.
But this food supply is highly vulnerable to climate change, says the first full-scale study into the problem. A team at the international research body ranked countries according to how dependent their people are on eating fish, how vulnerable the local fisheries are to climate change, and how well they are likely to be able to adapt (Fish and Fisheries, ).
Advertisement
“Northern countries will see the sharpest environmental impact from climate change,” says Edward Allison of WorldFish in Penang, Malaysia, “but economically, people in the tropics and subtropics will suffer most.”
Fourteen of the 20 most vulnerable countries are in Africa. This was a surprise, says Allison, because they include land-locked countries. However, some of these, like Uganda and Zambia, have important inland fish stocks, he says, and “perhaps 1 in 10 adults are employed in fisheries”.
The discovery gives a twist to Africa’s emerging food crisis. Climate modellers already knew that eastern and southern Africa are likely to face more droughts in future. The new study shows that, as the crops shrivel, the countries’ fish stocks will disappear too. “Fisheries are important for the poor, but fisherfolk are forgotten when it comes to adaptation to climate change,” Allison says.
Climate change also threatens tropical fisheries by changing river flows. The river Ganges yields millions of tonnes of fish a year to poor people in India and Bangladesh, a country that eats more fish than any other. But the river will lose two-thirds of its summer flow once Himalayan glaciers have melted.
In the Pacific, climate models suggest the El Niño temperature oscillation could become a near-permanent fixture, shutting down the currents that bring cold water rich in nutrients to Peru. Without them, the Peruvian anchovy harvest – one of the world’s great fish feasts – will collapse for good.
Some of the countries most at risk also have a woeful record of managing wild fisheries. Tony Pitcher of the University of British Columbia in Vancouver, Canada, and his team found “dismayingly poor compliance” with a 13-year-old UN code aimed at protecting the world’s wild fish stocks (Nature, vol 457, p 658). Countries whose fisheries are not only vulnerable to climate change but are also badly managed include Nigeria, Senegal, Ukraine, Vietnam and, in the bottom three on both lists, Angola.
