• The abundance of beluga in the Caspian Sea is decreasing.1,2 Beluga is on the decline in the Black Sea. In the Danube River, the last major spawning river for beluga in this region, the species is considered vulnerable in the lower reaches, critically endangered in the middle reaches, and extirpated from the upper reaches.3 Beluga is on the verge of extinction in the Sea of Azov.4
• Beluga sturgeon has lost 90% of their Volga River spawning grounds.5 The number of beluga sturgeon entering Russia's Volga River to spawn dropped from 26,000 annually in the period 1961-65 to 7,000 in the 1991-95 period.2 One source indicates that during 1998-2002, an average of only 2,800 individuals were observed..6
• In Kazakhstan’s Ural River, which is unhindered by dams, the number of beluga sturgeon entering the river system declined from 3,900 individuals in 1994 to 2,500 individuals in 2002. 7
• Illegal catch has been estimated at six to 10 and 11 times greater than legal catch in the Caspian and Azov Seas, respectively.8,9 Illegal fishing is one of the main factors causing the continued decline in beluga.2
• Catch of beluga once exceeded 14,000 tons in the early 1900s; catch levels in 1970 were only 2,800 tons while the 2003 catch quota amounted to only 155 tons.10,11,12,13
• Although hatcheries in the Caspian Sea proposed to release over 14 million beluga fingerlings in 2003, the estimated survival rate of these individuals is only 1-3%.14
• Trawl surveys conducted in the Caspian in 2001 found 64 beluga sturgeon in the 355 trawl catches conducted, for a ratio of 0.18 beluga per trawl tow.15,16,17 In 2002 a total of 38 beluga were caught in 333 trawl tows, for a ratio of 0.11 beluga sturgeon per trawl tow.18 Based upon these sources, this indicates a 39% decline in beluga sturgeon abundance between 2001 and 2002.19
• Recent surveys of beluga in the northern Caspian Sea have found relatively few mature fish.2,14,18,20 Trawl surveys in 2001 found only four mature adults and these were very young adults, just beginning the reproductive phase of their lives.18
• Due to a lack of food and pollution, only 4% of the beluga caught in the 2002 trawl surveys of Northern Caspian feeding grounds had full stomachs; in general, stomach contents consisted of algae, paper and cellophane packages. 18.19
• A recent study of organochlorine (PCB's, DDT, etc.) contaminant levels in Caspian Sea sturgeons found high levels in all species, with levels in beluga the highest. Effects of this contamination on beluga reproduction and human consumption have yet to be assessed.21
Click here to download the First Global Review of Sturgeon Fisheries published in the journal, Fish and Fisheries, by Caviar Emptor scientists and visit www.pewoceanscience.org/press/sturgeon for more information.
Compiled by Caviar Emptor, September 2005
1 Khodorevskaya, R. P. 1999. Formation of commercial stock of Huso huso in the Volga-Caspian region by hatchery reproduction. Journal of Ichthyology 39(9): 807-810. 2 Khodorevskaya, R. P., E. V. Krasikov, A. A. Fedin, V. A. Fedorov, and V. V. Shvedov. 2002. Abundance and distribution of the beluga Huso huso in the Caspian Sea. Journal of Ichthyology 42(1): 51-58. 3 Hensel, K. and J. Holcik. 1997. Past and current status of sturgeon in the upper and middle Danube River. Environmental Biology of Fishes 48: 185-200. 4 Chebanov, M. S. and E. A. Savelyeva. 1999. New strategies for brood stock management of sturgeon in the Sea of Azov basin in response to changes in patterns of spawning migration. Journal of Applied Ichthyology 15(4-5): 183-190. 5 Secor, D.H., V. Arefjev, A. Nikolaev, and A. Sharov. 2000.Restoration of sturgeons: lessons from the Caspian Sea sturgeon ranching program: Fish and Fisheries 1: 215-30. 6Armstrong, J.A., M. I. Karpyuk, T. De Meulenaer, S.V. Nash, and M. Pourkazemi, M. 2003. The status of beluga sturgeon (Huso huso) in the Caspian Sea, since it's listing in CITES in 1998. 7Armstrong, J.A. 2003. The current status of beluga sturgeon (Huso huso) in the Ural River (Kazakhstan). 8 DeMeulenaer, T. and C. Raymakers. 1996. Sturgeons of the Caspian Sea and the international trade in caviar. TRAFFIC International. 9 Vaisman, A. and C. Raymakers. 2001. The status of sturgeon resources in Russia. TRAFFIC Bulletin 19(1): 33-44. 10 Khodorevskaya, R. P., E. V. Krasikov, G. F. Dovgopol, and O. L. Zhuravlev. 2000. Formation of the stock of Caspian Acipenserids under present-day conditions. Journal of Ichthyology 40(8): 602-609. 11 TRAFFIC. 2000. Review of 10 species of Acipenseriformes, prepared for the Sixteenth Meeting of the CITES Animals Committee. 12 Raspopov, V. M. 1993. Age structure and population dynamics of the beluga, Huso huso, migrating into the Volga. Journal of Ichthyology 33(3) 105-112. 13 CITES 2003 export quotas. 14 Moiseev, A. 2002. Total Allowable Catch (TAC) estimation for sturgeon species in the Caspian Sea. 15 Only preliminary results from 2001 trawl surveys were initially released for public critique. Those preliminary results showed 28 beluga were captured in 159 trawls, for a CPUE of 0.18, which is the data referred to in Pikitch and Lauck (2002). In September 2003, CITES announced the final results from the 2001 survey , stating that 64 beluga were captured in 355 trawls, yielding the same CPUE, 0.18. 16Pikitch E., and L. Lauck. 2002. A Scientific Response to the CITES Justification for Setting the 2002 Total Allowable Catch of Beluga Sturgeon (Huso huso) in the Caspian Sea. 17Armstrong, J.A. and M. I. Karpyuk. 2003. Beluga sturgeon (Huso huso) in the Caspian Sea – a response to the proposal to list beluga as endangered under the U.S. Endangered Species Act. 18Report on Results of Complex Interstate All-Caspian Sea Expedition on the Assessment of Sturgeon Species Stocks, 2002. 19Pikitch, E. K. 2003. Comments on “Report on Results of Complex Interstate All-Caspian Sea Expedition on the Assessment of Sturgeon Species Stocks, 2002”. Document submitted to USFWS. 20Stone R. 2002. Caspian ecology teeters on the brink. Science 395:430-433. 21Kajiwara, N., D. Ueno, I. Monirith, S. Tanabe, M. Pourkazemi and D.G. Aubrey. 2003. Contamination by organochlorine compounds in sturgeons from Caspian Sea during 2001 and 2002. Marine Pollution Bulletin 46: 741 –747.
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