Royal Society Researchers - North Sea Cod Finished Thanks To Water Temps, W or W/O Fishing Bans

[hatrack]

Cod are doomed to disappear from the North Sea because of climate change and not just as a result of over-fishing, researchers have discovered. In the past 40 years the average temperature of the North Sea has increased by one degree centigrade with catastrophic effects on its delicate eco-systems.

Species of plankton, on which cod larvae feed, have moved away in search of cooler waters. The decline in cod stocks has led to an explosion in the populations of crabs and jellyfish, on which the adult fish feed. The shortage of predators at the top of the food chain has had a knock-on effect on flat fish, such as plaice and sole, whose offspring are eaten by crabs.

EDIT

The researchers studied the distribution of surface-dwelling copepod plankton on which young cod feed. Copepod’s numbers have declined by more than 60 per cent as the sea has warmed over the last four decades. Dr Kirkby said: “The plankton that young cod usually eat during March, April and May, a species of copepod that is the size of a grain of rice, prefer cold water and so they have become much less frequent as the North Sea has warmed.

“These copepods have moved north by about 1,200km (745 miles), or 30 km per year, and the plankton replacing them come later in the year, which is no good for the young cod. “The cod will not simply move north to follow the plankton, however, because the water there is too deep. “As top predators such as cod are declining, this appears to have had a cascading effect on the whole ecosystem.

EDIT

http://www.timesonline.co.uk/tol/news/environment/article6827389.ece

[Nihil]

1. K & R #5

:-(

[pscot]

2. There used to be cod in Puget Sound

but we rubbed them out.