Subscribe now

Earth

'Shares' in fish stocks halt commercial free-for-all

By Debora Mackenzie

18 September 2008

Collapsing fisheries can be saved from further decline by a radical management reform already used in Australia and New Zealand, suggests a new mega-study of global data

Fisheries are in bad shape: catches have fallen more than 10% in the past decade, a quarter of world fisheries have already collapsed, and if current trends continue, all of them will by 2048.

However, the new analysis suggests they may yet be rescued, by giving individual fishers an interest in maintaining the stocks.

Yet a massive overhaul of the EU’s Common Fisheries Policy announced in Brussels today makes no mention of the technique.

‘Free-for-all’

The problem with most fishing, says Chris Costello of the University of California at Santa Barbara, is that it is a free-for-all. Scientists assess stock sizes and recommend catches, “but then there’s a race to fish, as individuals try to get as much of the quota for themselves as possible”.

In a classic tragedy of the commons, there is no incentive for anyone to hold off, because then another fisherman will just take the fish till the quota is used up.

This leads to pressure for larger catches so fishermen can pay for the equipment, and results in damage to the marine ecosystem from smash-and-grab trawling and unintended “bycatch”, and cheating on quotas.

It also leads governments to subsidise their own vessels, allowing fishing to continue even after a stock is too depleted to be worth fishing, and virtually guaranteeing collapse.

Common interest

To avoid this scenario, since 1980, Australia, New Zealand, Iceland, Alaska and other fisheries have adopted “catch sharing”, mostly in the form of Individual Transferable Quotas, or ITQs, which guarantee individual fishers a fixed share of the total allowed catch.

This has been dubbed privatisation by some, but shares can also be granted to communities or cooperatives.

The idea is that fishers with a guaranteed cut needn’t race each other to grab their share, and can use smaller boats and more selective equipment. “Owners of ITQs should have an interest in the long-term health of the fishery, as a growing stock automatically means a bigger catch,” says Costello. But until now there was no conclusive evidence.

In an analysis of more than 11,000 fisheries worldwide, Costello and colleagues found that the 121 fisheries managed with ITQs were half as likely to have collapsed as fisheries overall. And the longer a fishery had ITQs, the less likely it was to collapse – declines in catches stopped and even reversed.

If all world fisheries had switched to ITQs in 1970, the team calculates, the number of collapsed fisheries would have stabilised at 10% by now. Instead it is growing.

Journal reference: Science (DOI: 10.1126/science.1159478)

Sign up to our weekly newsletter

Receive a weekly dose of discovery in your inbox! We'll also keep you up to date with New Scientist events and special offers.

Sign up