During the long period (1929–77) of water-level decline and consequent drying of the most favourable spawning grounds, the sturgeon population fell considerably.
The bottom is formed of a monotonously rippling sedimentary plain, broken only by a line of southern bars and shoals—some of which constitute the foundations for Tyuleny and Kulaly islands and the Zhemchuzhny shoals—reflecting underlying structural rises. Many rare and endemic plant species of Russia are associated with the tidal areas of the Volga delta and riparian forests of the Samur River delta.
By the end of the 19th century, Baku became known as the "black gold capital", and many skilled workers and specialists flocked to the city. It is reportedly the largest found in 25 years. The Caspian plays an important role in the region’s transportation: petroleum, wood, grain, cotton, rice, and sulfate are the basic goods carried, while Astrakhan and Makhachkala in Russia, Baku in Azerbaijan, Bandar-e Anzalī in Iran, Türkmenbashi in Turkmenistan, and Aqtaū in Kazakhstan are the most important ports. Adjacent Iranian littoral saltland vegetation from Zohary’s (1973) geobotanical map of the Middle East is also included since it represents a similar halophytic environment.
 By the 16th century, Europeans were aware of the rich oil and gas deposits locally. Sometimes they will haul out on islands, forming dense groups, typically at the ends of sandbars or peninsulas. Caspian seals are mostly piscivorous, meaning that they feed on a range of small fish, in particular kilka, and also crustaceans such as shrimp. Justification of Ecoregion DelineationThis ecoregion encompasses the Caspian depression of Kazakhstan, the Karabogaz Kol in Turkmenistan and includes the Volga Delta and surrounding semi-desert. In deep sea fishing, diving and well-tapping the extent to a depth less than 200 metres is notable, namely 240,000 km². The 10 Most Venomous Animals On Earth! The Caspian is of exceptional scientific interest, because its history—particularly former fluctuations in both area and depth—offers clues to the complex geologic and climatic evolution of the region. Because of their use by the three nations, median lines seem to be the most likely method of delineating territory in future agreements. Investigations of the sea are now coordinated by the Scientific Council of the Caspian Sea. Caspian seals use both the Sea’s shallow northern basin and its deeper waters in the middle and south, sometimes also entering the rivers feeding into the Sea. Its seafloor is, therefore, a standard oceanic basalt and not a continental granite body. Seals have more blood than other animals, and since blood cells carry oxygen, seals are able to dive for longer than other animals.
The Caspian seal is an endemic animal of the Caspian Sea.  By far the most numerous families in the lake proper are gobies (35 species and subspecies), cyprinids (32) and clupeids (22).
Especially impressive is the Kulandagh chink above the Kara-Bogaz-Gol Bay (300-320 m high).
In the North Caspian, the majority of the islands are small and uninhabited, like the Tyuleniy Archipelago, an Important Bird Area (IBA), although some of them have human settlements.
The Caspian Sea is 630 miles /1030 km/ long, and 175 miles /435 km/ wide. For the most part, the eastern shore of the middle Caspian is precipitous, with the sea destroying the margin of the limestone plateaus of Tüpqaraghan and Kendyrli-Kayasansk. Donations are tax-deductible as allowed by law. This number of species is relatively low for a body of water of this size. About 60% of the Khazar (former Krasnovodsk) Reserve area lies within the aquatory of the Caspian Sea. Sturgeons, including the beluga sturgeon, the largest freshwater fish in the world, inhabit the Caspian Sea in great numbers and yield roe (eggs) that are processed into caviar. The drainage basin of the sea covers some 1,400,000 square miles (3,625,000 square km).
ReferencesAtamuradov, K. I.
The Caspian turtle, although found in neighbouring areas, is a wholly freshwater species. , The convention grants jurisdiction over 24 km (15 mi) of territorial waters to each neighboring country, plus an additional 16 km (10 mi) of exclusive fishing rights on the surface, while the rest is international waters. The plateaus often form spectacular escarpments (chinks). Ogurja Ada is the largest island. Zohary, M. 1973. The Caspian basin, as a whole, is usually divided into the northern, middle, and southern Caspian, based partly on underwater relief and partly on hydrologic characteristics. Pp. It has no outlet so the surface level of water fluctuates a little. It was announced in October 2016 that Lukoil would start production from it.
Discoveries in the Hotu cave and the adjacent Kamarband cave, near the town of Behshahr, Mazandaran south of the Caspian in Iran, suggest human habitation of the area as early as 11,000 years ago. The northern (especially Volga delta), northeastern, and eastern coasts of the Caspian Sea lie on a major migration route between Europe and Asia. The development of the shipping industry in Azerbaijan is closely connected with the formation and progress of the oil industry. It is most saline on the Iranian shore, where the catchment basin contributes little flow. The sea is bordered in the northeast by Kazakhstan, in the southeast by Turkmenistan, in the south by Iran, in the southwest by Azerbaijan, and in the northwest by Russia. Animal life—which has …
Kluwer Academic Publishers: Dordrecht. The Sarykum barkhan which is a unique refuge for flora adapted to the loose sands of the ancient Central Asian deserts. Average annual temperature is 15.4° C. Annual precipitation is ca. These affect aquatic plants of the Volga Delta, such as Aldrovanda vesiculosa and the native Nelumbo caspica. The Caspian seal is found only in the Caspian Sea and is the only marine mammal that lives there.
A key problem to further local development is arriving a precise, agreed demarcation lines among the five littoral states. The largest are Chechen, Tyuleny, Morskoy, Kulaly, Zhiloy, and Ogurchin. 150 mm; frostless period lasts 260 days. Overfishing has depleted a number of the historic fisheries.