Farmed sturgeon 'only hope for caviar'

Mid-size beluga sturgeon like this are rarely seen (Image by Hans-Jurgen Burkard/Bilderberg) By Alex Kirby  BBC News Online environment correspondent in Atyrau, Kazakhstan A fish that can live for 150 years and grow to six metres (19 feet) in length appears doomed to extinction. The fish is the beluga, one of the seven species of sturgeon living in the Caspian Sea. It's pointless to imagine any longer that the sturgeon can survive here naturally Abish Bekeshev Environmentalists say there is no hope that any sturgeon can survive in the wild. But they say farming them for their caviar carries great risks. An estimated 95% of the world's caviar comes from the Caspian. But the problems besetting this landlocked central Asian sea are multiplying. It used to be shared by the Soviet Union and Iran, but the end of the Cold War saw Soviet control parcelled up between Russia, Kazakhstan, Turkmenistan and Azerbaijan. The sturgeon poachers' secret world Since the Soviet break-up, poachers have taken increasing numbers of sturgeon, including many immature fish. The rush to exploit the Caspian's massive oil reserves puts all the sea's wildlife under growing pressure. And the problem is being compounded by the arrival in the Caspian of an alien species, the comb jellyfish Mnemiopsis leidyi, which competes for food with the sprats (kilka) on which the sturgeon depend. The sturgeon are remarkable fish in their own right, apart from their value as producers of caviar for the luxury trade. They swim up to 1,500 km (950 miles) upstream to spawn. Belugas can weigh up to 1,200 kg in maturity. Abish Bekeshev used to head the natural breeding department at the Sturgeon Research Institute here. He said: "The biggest sturgeon I ever saw was 840 kg, about 3.4m long, and 56 years old. "I did hear of one 70-year-old beluga weighing 2,560 kg, but that may have been a legend. Either way, it's pointless to imagine any longer that the sturgeon can survive here naturally." Hatched to breedBeluga, the sturgeon most prized for its caviar, becomes sexually mature when it is about 12 years old. But most beluga caught nowadays are younger and have not spawned. Conservationists promote alternatives from paddlefish, wild Alaska salmon and whitefish (Image by Bill Reese) The two Atyrau sturgeon hatcheries release 6-7 million young fish (known as fingerlings) annually, when they are two months old and about 10 centimetres (6 inches) long. They estimate that 0.8-1% may survive. The proportion of artificially reared fish looks set to spiral if the caviar industry's plans are realised. An official at the fish cannery in Atyrau explained their ambitions. He said: "From 2003, instead of releasing the sturgeon we rear when they're fingerlings, we'll keep them to breed from. We'll make the beluga pregnant at seven years, the other sturgeon species at four. Odd fish"That way we hope to get 23-25 tonnes of caviar annually. I think it will taste different, though." He says international controls on selling wild-caught caviar will not apply to farmed fish.Abish Bekeshev says the whole concept is flawed anyway. "The female fish are given hormone injections to encourage them to become pregnant," he explained. "We should use sturgeon hormones for this - but we don't have enough sturgeon to provide them, so we use hormones from other species. "It's the same with the sperm: the fish are made pregnant using different sorts of sperm. There's now a tendency towards more hybrids than real sturgeon - they're mutants, freaks."  Source:   http://news.bbc.co.uk/2/hi/science/nature/2528557.stm More Stories:   Gofishtalk