Over the past few decades a revolution in fishing techniques and the growth of world population have caused a dramatic slump in fish stocks. It is a story which starts with Britain and the North Sea.
From Roman times until the early years of this century, the seas around Britain were famous for their abundance of sea life. But even when the Industrial Revolution began to create a mass-market for fish, stocks remained relatively stable. This was not because of conservation but incompetence: fishing methods stayed remarkably similar from Medieval times until well into this century. And on land, transport difficulties meant that for centuries fish only tended to reach much of the population after it was dried or salted.
The precursor to the modern chippy - Simpson's Fish Ordinary, a "fish and chop shop" - existed as early as 1723. But it was the arrival in Britain of commercial refrigeration in 1861, together with rapid urbanisation, that both created an appetite for cheap protein and provided the means to satisfy it.
"We like to think fish was the first protein-based fast food," said Arthur Parrington, general secretary of the National Federation of Fish Friers. "Sellers would fry it and peddle it on the streets. Dickens even made references to fried-fish warehouses in Oliver Twist."
Fish was nutritious, cheap, and gradually became easily available. In the recession of the 1930s there were 50,000 fish-and-chip outlets (today there are 8,500). Known as "pin money" shops, they were run by housewives from the front of their homes.
But despite the increasing demand, fish stocks did not drop dramatically, partly because of the temporary removal of trawlers from the seas during the First and Second World Wars. There seemed to be no reason to believe that the oceans would be anything but the source of an eternal harvest.
Then in the 1950s the tide turned, chiefly because it became profitable to catch fish for industrial products - oils, fishmeal, fertiliser and animal feed. Freezer trawlers which could gut and freeze huge quantities of fish on board were introduced. Technology-based industrial fishing was born.
Thirty years on, satellites enable trawlermen to predict the weather and sonars pinpoint shoals of fish. Huge nets hoover them up; in some parts of the world these are 50 miles long, with openings that could accommodate 16 jumbo jets.
The results have been dramatic. From the turn of the century the world's fish catch grew nearly twenty-fold. But it fell sharply in 1990 and has not recovered. Today the UN's Food and Agriculture Organisation reports that every one of the world's major fishing areas has either reached or exceeded its natural limits - and that nine of them are in serious decline.
The North Sea, once one of the world's richest marine areas, has been savagely affected. Every year the industry sucks up more than half the cod and haddock left there. Nearly three-quarters of young cod are caught before they have even started to mature. The stock of mackerel has crashed fifty-fold since the 1960s and fishing for herring had to be stopped altogether from 1977 to 1982.
Pollution and the destruction of wetlands - where fish breed - have made things worse. Sales of fish keep increasing, aided by consumer concerns about health and scares such as the beef crisis.
But the stocks are running down as boats move into new areas, fish new species and compete ever more fiercely. Tempers are rising. And so, inevitably, are prices.Reuse content