GENEVA - A global ban on wild caviar is spurring illegal trade and failing to conserve sturgeon stocks in the Caspian Sea, says Armen Petrossian, head of the company that introduced caviar to the West after the Russian Revolution.

Wild caviar exports this year are limited to 46 metric tonnes, 96 per cent of which comes from Iran. The Convention on International Trade in Endangered Species (CITES) refused to approve other sales to reverse an estimated 30 per cent drop in the number of Caspian Sea sturgeon in the last two years.

"Banning all exports from the Caspian gives no room for the region to respond to demand by legal means and leaves the door wide open to the illegal market," Petrossian said.

Next month, he will press Geneva-based CITES to approve export licences for a limited quantity of the caviar already collected this year.

As farmed caviar becomes more available, consumers will favour it over the often inconsistent quality of illegal caviar, Petrossian said.

He estimates that production of farmed varieties may triple, to reach 150 tonnes within five years.

The Petrossian business, founded in Paris in 1920, is considered the world reference for caviar prices and has annual revenue of about US$51 million ($76.2 million).

It owns restaurants and shops in Paris, New York and Los Angeles and sells a 50g tin of Imperial Persicus, the Iranian wild caviar, for US$391 to US$7600 per kg.

However, environmental groups, say sturgeon stocks are so depleted they are on the brink of extinction.

"We'll be urging CITES to keep the trade closed because the population is just not healthy enough," said Dawn Martin, executive director of SeaWeb, a Washington-based environmental group that campaigns to conserve marine stocks.

After 3000 years of humans catching the 27 different varieties of sturgeon, the fish "is the single most-vulnerable wildlife resource in the world," said Ellen Pikitch, executive director of the Pew Institute for Ocean Science in New York.

Caviar hasn't always been popular. When Petrossian's father and uncle offered caviar at an exhibition in Paris in 1931, visitors spat it out, he said.

Sturgeon is vulnerable as it lives in both salt and fresh water and scientists know little about its migrations.

Caviar is rare and expensive because sturgeon mature slowly, produce eggs at seven to 15 years old, and only every two to six years after that.

The beluga sturgeon is the world's most expensive fish, and takes 15 years to mature. It can live for a century in the wild and grow up to six meters, weigh a tonne and produce 10 per cent of its weight in roe.

Illegal trade in caviar worldwide, which is estimated to be worth as much as US$500 million a year has slashed sturgeon stocks in the Caspian.

At present, farmed caviar can't meet the demand created by the shortage of wild roe, said Alan Jones, who produces 10 tonnes of farmed caviar a year near Bordeaux in France and counts Cathay Pacific Airways and Carrefour SA among his clients.

Philippe Etchebest, whose restaurant at the Hostellerie de la Plaisance in St Emilion has a Michelin star, has been serving Jones' caviar for the past decade.

Farmed caviar, celebrity chefs, customs officials enforcing the trade and consumer education are all vital to save wild sturgeon stocks, Petrossian said.

Dearest Roe

* Caviar is produced by sturgeons, of which there are 27 varieties.
* Illegal trade has slashed sturgeon stocks in the Caspian Sea, source of the best caviar.
* A 50g tin of Imperial Persicus caviar from the Caspian sells for $585.