'Cod delusion' leaves devastated stocks on the brink

'Cod delusion' leaves devastated stocks on the brink

17:19 26 September 2008
NewScientist.com news service
Debora MacKenzie

Fishing vessels on the Grand Banks of Newfoundland are this week destroying the best hope for years that the region's cod fishery, once the world's most abundant, might yet recover.

And at a meeting in Vigo, Spain, governments have rejected a simple measure that might have given the cod a fighting chance.
Cod fishing on the banks has been banned since 1992, after overfishing destroyed the stocks. Despite this, the cod have shown no signs of recovery. This was initially blamed on subtle, permanent changes to the ecosystem.
Baby by-catch

But in recent years another culprit has emerged – the few young cod still being spawned are being swept up in nets intended for other fish before they can spawn themselves. On average some 1500 tonnes of three-year-old cod are destroyed as by-catch in this way on the southern banks every year.

Two-thirds of this is caught outside Canadian waters, where fishing is managed internationally by the Northwest Atlantic Fisheries Organisation (NAFO).
Last year, NAFO ordered a 40% cut in cod by-catch in 2008. But, says Robert Rangeley, a fisheries scientist working for the conservation group WWF, data so far this year suggest that target has already been caught – and there are three months of fishing left to go.

This could be because the number of babies spawned by adult cod each year varies widely for reasons scientists do not yet understand. And 2005 was a bumper year, with possibly six times more fish surviving than in previous years.

"If they were left to grow up, they could become the nucleus of a real recovery," says Rangely. But this year those fish became big enough to be by-catch.
Missed opportunity

Meanwhile a discovery by scientists at the Canadian Department of Fisheries and Oceans in St John's, Newfoundland, that could have slashed by-catch is being ignored.

Boats fishing for yellowtail flounder catch 85% of the Canadian cod by-catch. Joanne Morgan of DFO told NAFO last June that flounder nets catch the most cod between August and November, with a peak in September and October.

If the fishery was to shut for just those months, Canada's cod by-catch, a third of the total, could be cut by two-thirds – with no loss of flounder, which can be caught for the rest of the year. But the measure was not even discussed at NAFO's annual meeting this week.

Instead the assembled governments increased the permitted catch of flounder, and did not cut quotas for thorny skate, a catch that accounts for much of the cod by-catch outside Canadian waters and which NAFO's scientific advisors had wanted halved.
That means more dead, baby cod next year.