At stake is the multi-million- pound trade in the delicacy which more than any other carries the cachet of luxury: caviar. Money is not the only prize. This form of black gold earns Iran only tens of millions of dollars a year in foreign exchange - a drop in the ocean compared with oil exports, measured in billions. As significant is the reputation of the Islamic Republic of Iran as a reliable source of a high quality product.
The market has been rocked by the disintegration of the Soviet Union. Once all Soviet production was marketed by a single trading house. Now all four former Soviet republics bordering the Caspian - Russia, Azerbaijan, Turkmenistan and Kazakhstan - are producing their own caviar. In their rush for hard currency, they have been flooding the market with caviar of often dubious quality, according to the Iranians.
Last August, representatives of the five producer states met in the Iranian port of Bandar Anzali to discuss how to co-ordinate pricing and fisheries policies. The meeting had the makings of a cartel, but did not achieve much. Now each producer is seeking to maximise profits in the way it sees best: the Iranians through strict quality control, the former Soviet republics by selling as much as possible.
Caviar as a delicacy used to be reserved for shahs and tsars. Over time their imperial majesties began to share their pleasure with the royal houses of Europe, to whom they presented caviar as gifts. After the revolution in Russia, caviar became almost daily fare. Out of an annual catch of 700 tons, less than 100 tons were exported. Iran produces about 240 tons a year, of which 200 tons is exported through the sole trader, the state owned Shilat Trading Corporation.
Their export markets differed too. Since the 1979 Islamic revolution, the United States has banned direct imports from Iran. Most Iranian caviar goes to Europe. Duty also varies. On caviar from the former Soviet Union it is 30 per cent, on that from Iran it is 12 per cent. Iran can therefore sell its product at a higher price.
But it is on quality that Iran believes it has the competitive edge. Traditional methods still bring the raw eggs of the sturgeon to the silver spoons of the rich. At the Newisi fishing station at the eastern end of the south Caspian shore, the fishermen leave before dawn in their small craft to check the nets. This is the season for sevruga, the most common of the three types of sturgeon found in the Caspian. The others are asetra or ocietre and the grandest of all, beluga.
On one of the fishing boats, four men pulled up nets that stretched for 3kms (two miles) at right angles to the shoreline. Every so often, they find a mature fish caught by the gills in the mesh. The fish are hauled on board, their nozzles bound and then they are lowered over the boat again so that they can arrive alive and fresh at the caviar processing station on the beach. The men reject more modern fishing methods. Trawling would destroy stocks, they say.
The men can tell immediately from the shape of the belly which are the egg-bearing females and which are males. The latter are sold for their flesh.
Two men lift a female fish on to a platform, still alive. One makes a swift incision from below the gills down the belly. They then slowly lift out the eggs, contained in two membranes, packed one on either side like grey ox tongues. These are carefully lifted into a stainless steel vessel, washed, placed on a sieve to remove the membrane, weighed again, then taken next door where another mixes the eggs with pure salt, ground fine like icing sugar. This preserves the caviar and gives it its salty taste.
The eggs are graded, packed in tins, and refrigerated. It takes less than 10 minutes from opening the fish to packing the eggs. They are then taken to the central depot, where they are inspected, graded, and packed for shipment to Tehran.
The supervisor of the packing station, Gholamreza Eshramdi, says the industry has changed since the revolution. 'The fishermen are better looked after, and better paid. And we are more sensitive to the ecology of the industry and fish husbandry.'
For the first time, sturgeon are being bred in captivity and the smelts released into the sea once they reach a finger's length. But it is too early to judge the success of this experiment.
The fishermen are confident that the special quality of the water in the Caspian, with its high potassium content, is unmatchable. And they extol the qualities of the clear, deep Iranian waters as against the more polluted, shallow waters of the northern Caspian.
The challenge is finding new and reliable markets. Italians consume seven to eight tons a year, but buy it through suppliers, such as the Geneva-based Caviar House.
'Our problem is not selling,' says Akbar Alireza, the export manager. 'It is selling to the right people. We do not want buyers to purchase our caviar, then mix it with stuff from the ex-Soviet republics and pass it off as Iranian.'