Cod hit by North Sea warming

Posted: 28 November 2000

Global warming has been blamed, with overfishing, for the disastrous decline of cod stocks in the North Sea.

North Sea cod. Credit: CEFAS.

Cod catches have fallen from 200,000-300,000 tons a year in the 1980s to a 1990-98 average of 100,000 tons. Over the same period, North Sea surface temperatures have risen, probably as a result of global warming. Scientists at the UK Centre for Environment, Fisheries and Aquaculture Science (CEFAS) have shown that the temperature of the North Sea in spring affects the survival of young cod during their first year of life.

Over-exploitation of cod is another key factor. A high percentage of the fish caught are under four years old, which means that few survive to reach sexual maturity. A 40 to 60 per cent reduction in catches is now being recommended.

EU limits in 1999 were set at 80,000 tons for British fishermen, and a general outcry resulted. Yet only 50,000 tons were landed in the end, and only 60 per cent of the lower 2000 quota is likely to be landed. Some fishermen also blame the depleted cod stocks on the amount of seismic activity undertaken in the search for oil and gravel at sea.

See article by CEFAS: What's happening to North Sea Cod?

Read about the Cod Fish.