The huge profit margins have attracted criminals

The sturgeon is the fish that produces caviar eggs and the Caspian Sea is where most of them live.

The year 2000 was another bad year for caviar. The Caspian Sea used to teem with sturgeon, some of them weighing as much as 1,000kg - massive, prehistoric fish bursting with glittering black eggs.

These days even fish a quarter of that size are few and far between.

Dwindling stocks

Russia is the biggest producer among the Caspian Sea littoral states, but its catch last year was little more than 60 tonnes. Ten years ago a harvest of 1,000 tonnes was nothing out of the ordinary.

Part of the problem is co-ordination of policy and that is one reason why experts and officials from the Caspian states - Russia, Azerbaijan, Iran, Turkmenistan and Kazakhstan - together with others from as far afield as China, the United States and France, are gathering in Moscow.

Russia wants to impose an immediate moratorium on all fishing of sturgeon. Its stocks must revive, it says, or the sturgeon faces extinction.

But the real problem is how to stop the pirate fishermen.

Caviar smuggling in the Caspian Sea is big business. The mafia gangs run hi-tech operations and haul in 10 times the states' official harvest.

Profits are estimated at around $200m a year. An agreement in Moscow will be of little use unless more is done to police the waves.