Increasing Population and Wealth Are Death to Fish

Fish represent an important source of food for humans and historically have had the economic advantage of needing only to be harvested. Yet in a nearly classical Malthusian situation, the fish stock has not been keeping up with population growth, especially as the world's increased wealth has created new technologies for tracking and harvesting fish. A new study has raised the alarm about numerous fish species in the Mediterranean that may be on the verge of extinction.

The study released Tuesday by the International Union for Conservation of Nature says almost half of the species of sharks and rays in the Mediterranean and at least 12 species of bony fish are threatened with extinction due to overfishing, pollution and the loss of habitat.

Commercial catches of bluefin tuna, sea bass, hake and dusky grouper are particularly threatened, said the study by the Swiss-based IUCN, an environmental network of 1,000 groups in 160 nations.

"The Mediterranean and eastern Atlantic population of the Atlantic bluefin tuna is of particular concern," said Kent Carpenter, IUCN's global marine species assessment coordinator.

He cited a steep drop in the giant fish's reproductive capacity due to four decades of intensive overfishing. Japanese diners consume 80 percent of the Atlantic and Pacific bluefins caught and the two tuna species are especially prized by sushi lovers.

Given the radiation pollution of the ocean near Japan, it is likely that the demand for Mediterranean fish will go up, not down, in the near future.

The U.N. Food and Agriculture Organization says fish stocks continue to dwindle globally despite increasing efforts to regulate catches and stop overfishing.

As I have noted before, the long-term consequence of over-fishing will be an ever-increasing dependence on farmed fish, but there are relatively few species that are known to be well-adapted to current fish farming methods.