Caspian Sea 2011

State of the Environment of the Caspian Sea

About 50 per cent of Beluga catches now occur in the Ural River Basin, whereas 15 years ago, 50 per cent were caught in the Volga River Ba- sin, 25 per cent in the Ural River Basin and 23 per cent around the south Caspian shoreline in Iranian waters. Catches of Russian sturgeon ( Acipenser guelden- staedtii Brandt & Ratzeburg, 1833) were exception- ally high in the 1970s – up to 12 thousand tonnes annually. By the beginning of the 1990s, the figure had dropped to between five and seven thousand tonnes per year. At that time, Russian sturgeon was the main commercial sturgeon species in the Caspian, constituting nearly 50 per cent of the to- tal sturgeon catch. In recent years, catches have been sharply reduced - in 2008, the total official catch of Russian sturgeon was only 124 tonnes. Persian sturgeon ( Acipenser persicus Borodin, 1897) was for a long time included in statistics re- lating to Russian sturgeon, but from 1990, sepa- rate catch data on the species has been available. During the twentieth century, the number of Per-

sian sturgeon caught was significantly lower than Russian sturgeon and Stellate sturgeon – these two species formed between 80 and 90 per cent of total sturgeon catches in the 1970-90 period. Total annual catches of Persian sturgeon did not exceed 1.5 thousand tonnes. Due to the large re- lease of Persian fingerlings by Iran, catches were more or less stable in the 1990s, with about 400- 500 tonnes caught annually in Iran, accounting for 70 per cent of the total annual Persian sturgeon catch. In subsequent years, catches have been re- duced to 108 tonnes annually for the whole Cas- pian Sea (data relates to 2005). Stellate sturgeon ( Acipenser stellatus Pallas, 1771) is another sturgeon species of great economic importance. Its annual catch was about five thou- sand tonnes in the early 1990s, while at the peak of sturgeon catches in the 1970s, this figure was between 10 and 13 thousand tonnes. In 2003-04 the annual Stellate sturgeon catch was between 200 and 300 tonnes. Stellate sturgeon is small compared to other Caspian diadromous stur-

Fragmentation of the Volga river over the last 60 years

36° E

48° E

36° E

48° E

1934

Today

60° N

Beloye Lake

Verhne Volzhinskiy Beishlot

Rybinsk

Kostroma

Perm

Tver Ivankovskoye Reservoir

Cheboksary

Izhevsk

Gorkiy

Moscow

Kazan

Kazan

Nizhniy Novgorod

Moscow

Naberezhnye Chelny

Sturgeon spawning grounds on the Volga Hectares

Samara

52° N

Kuybyshev

52° N

4,000

Balakovo

Saratov

Saratov

3,000

Volgograd

Shoreline of the Caspian Sea in 1934

Stalingrad

2,000

48° N

1,000

Main dams 0 200 km

Astrakhan

Astrakhan

CASPIAN SEA

0

CASPIAN SEA

1934 1999

Sources: Caspian Environment Programme, 2002; UNESCO,2004.

44° N

20

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