The North Sea from crystal clear fishing waters to an industrial quagmire
Ten thousand years ago, the North Sea, the sea with the richest stocks of fish in the world, was a tundra. In the ice age the water level was 50 metres lower than today. The North Sea is a shallow sea therefore with 75% of it no deeper than 50 metres.
Thousands of years ago the North Sea was one of the biggest fish reservoirs of Europe and was crystal clear. Today it has become a muddy industrial pool. Divers usually have no more than one metre of visibility. This muddy state of the water is mainly the result of overfishing. Along the North Sea coast there were once immense oyster banks with their large filtering capacity that before the Second World War had been plucked empty and damaged by the enormous trawl nets. Oysters consumed enormous amounts of plankton filtering the shallow waters of the North Sea.
The great whale disappeared from the North Sea, because the mussels disappeared from the deltas. In the past one could see porpoises - sometimes in groups of six, they are a rare sighting today. The Rhine Delta sturgeon has also completely disappeared. Atlantic salmon has become a great rarity in the rivers running into the North Sea. Red tuna has as good as completely disappeared from the North Sea. 100 years ago it was possible to catch ray fish as big as a man. No longer. The population of hake and herring have shrunk by 90%. The North Sea was fished empty of mackerel in 1970 and it never reappeared. And North Sea sole once grew to be 40 years old, now barely any are caught that are older than six years old.
In the Western part of the channel where the water is still clearer, there lie concealed in the sea stunning coral and sea fans. Norwegians have calculated that 40% of this coral has already been seriously damaged by trawl nets and that it will take 100,000 years for them to recover.
When you look at the water along the Belgian and Dutch coast you see brown foaming waves. 30 years ago it was completely different. The foam then was still white!