The federal government yesterday identified six foreign countries it said engaged in illegal fishing during the last two years, including the illicit harvesting of valuable and endangered stocks of Atlantic bluefin tuna.

The six nations named in a report by the National Oceanic and Atmospheric Administration — France, Italy, Libya, Panama, China and Tunisia — were the first the United States has ever specifically identified as violators of international fishing regulations.

The six nations now face potential trade sanctions from the United States, including a possible ban on the sale of their seafood in this country.

NOAA officials in a statement said they planned to engage the six nations in talks on potential corrective actions to stop illegal, unregulated and unreported fishing.

"Illegal fishing is a global problem that is depleting fish stocks and hurting the economies of nations and livelihoods of people who depend on sustainable fishing," said Jim Balsiger, an assistant administrator of NOAA's Fisheries Service. "Our report is part of stepped-up efforts called for by Congress to work with other nations to stop illegal fishing on shared fish stocks."

The majority of violations identified in the NOAA report involved illegal or unregulated catches of bluefin tuna, a fish prized for its use as sushi and which has been severely depleted because of its popularity.

Scientists and environmentalists have focused particular attention on tuna fishing in the Mediterranean Sea, one of two spawning grounds for the Atlantic bluefin and an area where the fish have been hunted relentlessly.

For fishermen in Gloucester and other fishing communities in Massachusetts, bluefin have long been a valuable resource, but overfishing in other parts of the world have reduced numbers of the ocean-roaming species.

"We know that there are two stocks of Atlantic bluefin tuna, one that spawns in the Mediterranean , and one that spawns in the Gulf of Mexico. Scientific studies have shown that these two stocks mix in the North Atlantic," Monica Allen, a NOAA spokesman, said yesterday. "The severe overfishing of the Mediterranean and eastern Atlantic stock can impact the bluefin tuna found off the North American coast, and therefore hurts traditional commercial and recreational fleets in Gloucester."

The basis of the report was two years of data collection by NOAA through collaboration with foreign governments, environmental groups, the public and Regional Fisheries Management Organizations, the groups that manage agreements for international fisheries.

Specific violations outlined in the report involving bluefin include:

Unreported catches by French fishermen using driftnets — large free-floating nets prohibited for bluefin use.

The use of spotter planes and other prohibited gear by Italian fishermen.

Libyan vessels fishing after the close of the season and failing to use Vessel Monitoring Systems.

The Chinese government failing to report bluefin catches.

The use of driftnets to catch bluefin by Tunisian boats and subsequent failure to report landings.

Unauthorized fishing of a variety of tuna species by Panamanian vessels.

Patrick Anderson can be reached at panderson@gloucestertimes.com.