Mark Kurlansky

If ever there was a fish made to endure, it is the Atlantic cod—the common fish. But it has among its predators man, an openmouthed species greedier than cod.

Man wants to see nature and evolution as separate from human activities. There is a natural world, and there is man. But man also belongs to the natural world. If he is a ferocious predator, that too is part of evolution. If cod and haddock and other species cannot survive because man kills them, something more adaptable will take their place. Nature, the ultimate pragmatist, doggedly searches for something that works. But as the cockroach demonstrates, what works best in nature does not always appeal to us.

The ocean floor left behind is a desert. Any fish swimming in the vast area of these nets is caught. The only control is mesh size. Fish that are smaller than the holes in the net can escape. While mandating minimum mesh sizes has become a favorite tool of regulators, fisherman often point out that once the back wall of the cod end has a good crop of fish in it, few fish of any size can escape, regardless of how big the mesh. Millions of unwanted fish—undesirable species, fish that are undersized or over quota, even fish with a low market price that week—are tossed overboard, usually dead.

As long as fisherman can catch a fish, they resist the idea that the species is in trouble. But with cod, they all recognize that there is a problem.