Bottom-feeder that keeps caviar prices rising

Another LifeThe natural history of Christmas, to be serialised annually in this column until every conceivable ingredient has been dealt with, focuses this year on what I presume is a must-have nibble at all the best parties, even as the economy is sliding under the table.

It is prompted by reports that the price of beluga caviar has risen over the past month from £340 (€471) to £495 (€686) for a 50g jar in one of the few West End emporia licensed to import it. Even the New York gourmet store Caviar Russe regrets that these particular "pearls of the Caspian Sea", normally $245 (€167) an ounce (28g), "are not available at this time".

Caviar cognoscenti, of whom Ireland must now have several at least, will give their chins a little toss at the plight of the poor beluga-chewers, since they will already have laid down a small cache of (probably smuggled) almas caviar in the bottom drawer of the bar-room fridge. Almas is the golden eggs of Oscietre sturgeons that have dodged the Caspian gill-nets for 60 years or more and thus, being two metres long and exceptionally rare, yield caviar priced from about €1,400 for 50g and sold for years ahead.

Almas eggs are much smaller than the pea-sized, melt-in-your-mouth, ballbearing-coloured orbs of beluga and are said to taste delicately of "walnuts and cream", which seems a bit of a let-down when one had braced one's palate for something exquisitely fishy. But then, unfertilised sturgeon eggs apparently taste of nothing very much when fresh from their caesarian - it's the salting that brings out the flavour.

STURGEON LOOK SOMEWHAT like giant pike, but lack the rapacious temperament. They're an ancient fish, largely unchanged in 100 million years, with a cartilaginous backbone, an armoured head and a snout with barbels, with which they root about for food in the sea or river bed, or pursue small fish such as anchovies. Beluga (Huso huso) is just the greatest of the several sturgeon species in the Caspian Sea, many now hatchery-bred, which together supply nine-tenths of the world's caviar. When the USSR broke up, fishermen in the sea's former Soviet coastal states - Russia, Azerbaijan, Kazakhstan and Turkmenistan - embraced free enterprise as fast as they could set their gill-nets (Iran is their remaining neighbour on the southern shore). By 1997, concern over illegal trade and unsustainable harvesting prompted the 170-nation Convention on International Trade in Endangered Species (CITES) to take sturgeon under its wing.

In 2005, the US Fish and Wildlife Service banned the import of beluga caviar and meat from anywhere around the Caspian and Black Seas. The loss of their biggest market forced most of the sturgeon states into conservation and control programmes to earn export quotas from CITES. This year, some 3,700 kilos of Caspian beluga caviar is being legally exported (1,000 kilos of it from Iran).

BUT HUSO HUSO is just one of almost a dozen sturgeon species under CITES quotas. Iran is exporting 38,000 kilos of caviar from Acipenser persicus, the sturgeon most abundant in the southern Caspian, and Russia takes 20,000 kilos from another kind, A. gueldenstaedtii. Bulgaria farms its sturgeon and exports more than 5,000 kilos of caviar from half a dozen species. Check the labels for CITES approval (or settle for cheap Icelandic lumpfish caviar, dyed red or black to taste).

None of this tells you about Ireland's three-metre sturgeon, Acipenser sturio, the only species to live in fully saline water. It was once fairly common around western Europe, spawning in every suitable river. According to the splendidly-named Wallop Brabazon Esq, in 1848, while "not at all numerous . . . [ sturgeon] are generally caught along the east coast of Ireland in the sandy Bays, where they are often left dry by the tide, and in trawl nets off those bays. I have seen some very fine ones, three of which were caught in Dundalk Bay, off Lurgan green . . . The Sturgeon in Ireland is a Royal fish, and each of these was sent up to Dublin Castle, the one last taken in Dundalk bay was forwarded to Buckingham Palace, as it was in remarkably good condition."

They continued to be caught off the east coast, but more and more rarely. The last one came up in a trawl off Ardglass, Co Down, in 1980, and was the biggest of the century. A small population, based on the River Gironde in the Bay of Biscay, was thought to have died out in the 1990s, but a full-sized sturgeon caught in Swansea Bay in Wales in 2004 had to have come from somewhere. Now solitary and rare, they roam Atlantic coasts from Morocco to the north of Norway, nuzzling the bottom quite near to the shore and looking for a partner to make caviar.