The entire 650-km length of shore and inshore waters of the Caspian Sea in Iran, from Astara on the border with Azerbaijan in the west (38°25'N 48°52'E) to the border with Turkmenistan, c.35 km north-north-west of Gomishan, in the east (37°21'N 53°57'E). The shore is almost entirely a narrow, hard, sand beach backed by low sand-dunes, except in the extreme west where there are stretches of shingle, and at one point to the west of Alamdeh (central coast) where there is a small area of rocky shore. The salinity of the Caspian is c.12-13 p.p.t. and the inshore waters are shallow. Between 1866 and 1933 the water level fluctuated between 25.2 and 26.0 m below sea-level. In the early 1930s, however, following the construction of several major dams on the River Volga in the former U.S.S.R., the level started to fall and this continued almost without break (other than seasonal fluctuations) until 1977-1978, when the level had reached 28 m below sea-level. Then began a sudden and rapid rise, averaging over 10 cm per year. By the end of 1991, the water had risen by c.1.8 m, bringing the level back almost to that of the 1930s. In the mid-1970s, when the sea was at its lowest, the beach was generally 30-50(-100) m wide, but by 1992 most of the beach had been submerged and the sea was invading the adjacent vegetated dunes. There remains considerable uncertainty about the cause of this sudden rise in level. It has been argued that it was deliberately engineered by the Government of the former U.S.S.R. in an effort to restore the sea to its original level. Two major engineering works could have contributed: the closing of Karabogaz Bay in the east Caspian in 1978 (thereby reducing the loss of water through evaporation), and the diversion of two Siberian rivers into the Ural river (thereby increasing the inflow of fresh water). According to some calculations the closing of Karabogaz Bay could alone have been responsible for a rise in sea-level of 40-45 cm, but there is also a strong body of opinion that the rise in sea-level is a natural phenomenon and merely part of a long-term cycle. The Caspian supports a major fishery. Land ownership is public.
See box for key species. The area is important for a wide variety of migratory waterfowl, notably grebes, cormorants, diving ducks and gulls in winter, and terns on passage. The sea is used extensively as a day roost for wintering surface-feeding ducks which feed at night on freshwater marshes and rice fields on the coastal plain. Large numbers of shorebirds stop over briefly along the beach in spring and autumn, but rather few winter. The most important stretches of shoreline for waterfowl are the Miankaleh Peninsula (see site 023) and the coast north of Gomishan (see site 024). Haliaeetus albicilla remains fairly common throughout the South Caspian region, especially in winter, and frequently scavenges along the shore or fishes in inshore waters. Small numbers of Plegadis falcinellus occur on passage. Land ownership is public.
Non-bird biodiversity: None known to BirdLife International.
BirdLife International (2021) Important Bird Areas factsheet: South Caspian shore, from Astara to Gomishan. Downloaded from http://www.birdlife.org on 02/03/2021.