Experience with other fisheries, such as the collapse of the cod population of the Grand Banks off Newfoundland in 1992, has shown that the dynamics of an ecosystem can change when a top predator is removed completely.

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Faced with collapsing fish populations, whether the disappearance of the cod fishery on the Grand Banks off Newfoundland or the failure of the North Sea herring fisheries, the reaction has been one of half-hearted measures: too little done too late in a chain of endless procrastination excused by the need for ever more scientific research.

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Barmac's Ardersier yard has been building two 'topside' deck modules for the floating rig being fabricated for the development of the Terra Nova field, on the Grand Banks, off Newfoundland.

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In the early 1990's, cod stocks in the rich fisheries of the Newfoundland Grand Banks collapsed -- some to as little as 1 percent of their historical levels -- because of over fishing.

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