It is one of the oldest species of fish in existence, going back to the age of the dinosaurs. Each fish can typically grow up to 15ft long, with some living 80 years or more, giving rise to them being called the Leviathan or Methuselah of freshwater fish. Add to this slow growth and reproductive rates, and bounteous numbers of sturgeon are never going to be likely. But the so-called "black gold" that lies within sexually mature females means that the species, unless rigorously policed, edges ever closer to extinction.
It has already come close with American sturgeon, the greedy over-fishing of which led to the burgeoning Caspian Sea caviar economy. This now provides 90 per cent of the world's caviar, but sails towards its own end unless a longer-term vision is adopted. According to the World Wide Fund for Nature, the sturgeon catch has declined by 96 per cent in the last 20 years.
This month, Cites (the Convention on International Trade in Endangered Species) issued its new catch and export quotas in a bid to curtail excessive sturgeon fishing. The quotas are below 2007 levels and have seen Iran's caviar quota for Persian sturgeon cut by 1,000kg. Setting quotas has been a frustrating business at best over recent years, especially since the dismemberment of the Soviet Union. If Iran and the USSR once invested heavily in controlling fish stocks, such progress has broken down now with the independence of the Caspian Sea states of Azerbaijan, Turkmenistan and Kazakhstan.
In 2001, for instance, Cites halted trade until a scientific survey of stocks was completed and a common management and conservation plan put in place as part of a "Sturgeon Resolution". Trade resumed in 2002 and 2003. But Cites was unable to publish quotas in 2004 because sturgeon-fishing states failed to comply with the resolution (Iran, also on the Caspian Sea, is not subject to Cites control, but retains a functioning management system).
In 2005, the US took no chances and banned the import of Caspian Sea beluga caviar – not the only variety but considered the finest – altogether. In 2006, Cites was, again, unable to approve quotas, a ban that was only partly lifted last year. Iranian fisheries ministry scientists, meanwhile, are predicting that, despite hatcheries trying to replenish stocks, Caspian Sea sturgeon will be extinct in 14 years.
"It's a question of taking control of the situation, which is pretty dire – most sturgeon populations are at a historic low, especially in the Caspian Sea," says Julia Roberson, programme manager at the ocean-conservation organisation SeaWeb. "We need to get the message across that wild caviar is simply not an ethical option – by restaurants removing it from menus and supermarkets from shelves. It's a luxury we can live without."
Not, it seems, if demand is anything to go by. Quotas, even when effective, only apply to the legal trade, which already struggles to meet sanctioned levels, not least because of the mismanagement of the Caspian Sea, including blocking its primary tributary, cutting access to spawning grounds, and environmental damage due to industrial contamination. Poaching and the illegal trade in caviar continues unabated: the caviar black market is estimated to outstrip the annual £50m legal trade by 10 to one.
And small wonder. To call sturgeon roe, or caviar as it is better known, "black gold" is no exaggeration: around four ounces of beluga caviar can be traded for an ounce of the yellow metallic variety. Its price is consistent, too: beluga costs around £100 per 50g, regardless of the state of the economy. And if, two centuries ago, the Hudson river teemed with sturgeon so plentifully that saloons served the fish eggs free of charge to stimulate drinking (caviar is up to 8 per cent salt), now the fish's rarity only serves to drive up caviar prices, which encourages a frenzy of buying and more fishing.
Nor has caviar's image been dented. Caviar is the Rolex of fine dining, as much a symbol of wealth and success as the status timepiece – a byword for high living even among those who can't afford it. The fat City bonuses of recent years will have seen a spike in caviar sales, as those with fat wallets put their money where their mouths are. It's no surprise that 95 per cent of the caviar market is accounted for by the world's richest countries: the EU, US, Japan and Switzerland . "Everyone indulges in the millionaire dream," says Ramin Rohgar, managing director of Imperial Caviar. "But it's better to love caviar for its taste rather than its image."
At least caviar's reputation should help one prong of the save-the-wild-sturgeon lobby's attack: to educate consumers about eco-friendly roe alternatives. North American suppliers in particular are attempting to reintroduce substitutes for imported caviar: the roe from paddlefish, bowfin, trout, North Atlantic salmon and whitefish have all been touted as flavoursome, sustainable alternatives. But none has the cachet of sturgeon roe.
"It's true that for some, only wild caviar is considered 'real' caviar," says Roberson. "But while other options are cheaper, they are still relatively expensive, which may help retain that kudos. And the quality is improving hugely. Then there is caviar from farmed sturgeon, which didn't have a reputation for either luxury or quality. But recent advances are changing that – in blind taste-tests chefs rank it just as high."
Certainly, aquaculture – the farming of sturgeon, increasingly popular in Spain, California, Uruguay, China and France – may provide a more convincing alternative to ersatz sturgeon caviar. Although there remains a degree of snobbery that distinguishes between wild and farmed caviar, the conservation efforts of companies such as Caviar House & Prunier, with a farming operation in Bordeaux, are providing commercially viable models that may relieve pressure on Caspian Sea stocks, and perhaps even end the black market. Even the hardnosed Iranian government is offering interest-free lending and expertise to investors to open sturgeon farms in Iran's ideal waters.
According to Rohgar, the sturgeon species used may mean that the size and colour of the farmed eggs may not match the best wild caviar, but, crucially, the flavour does. The battle is now one of perception. "When they're properly introduced to it, many top chefs, even caviar connoisseurs, are more than happy with aquacultured caviar, especially as more consider ethics," says Rohgar. "What snobbishness remains is in part because of farmed salmon, which is produced on such a huge, industrialised scale that it's a different product to the wild kind. People expect the same difference in caviars, but sturgeon are sensitive fish that need to be bred in conditions much the same as in the wild. We're moving towards a time when the only caviar available will be farmed, and with it will come new competition for quality and price."
Indeed, according to Simon Shepherd of Caspian Caviar, farmed and wild caviar is often indistinguishable – it has had samples genetically tested to prove the difference to some buyers. It is taking time and big money to make farming work, though. It's an expensive, high-tech business. If, traditionally, roe is harvested once a sturgeon is estimated to be sexually mature – by removal of the ovaries, killing the fish in the process – companies now microchip fish to allow them better to estimate the ideal harvesting time. Prunier has introduced ultrasound scanners to assist in this process. The next step may be the application of as yet experimental techniques that will allow the surgical removal of roe from living sturgeon, allowing it to live on and produce more. Presently, the process destroys the membrane that gives caviar its characteristic pop.
"The technology of farming sturgeon is still taking baby steps," says Peter Rabeiz, managing director of Caviar House & Prunier, "but it is advancing, both to protect the species and reduce the stress on the fish. But there is still work to be done to encourage consumers to switch to farmed. People who insist on wild caviar just don't know better."