The Sea of Azov is a sea in Eastern Europe connected to the Black Sea by the narrow Strait of Kerch, and is sometimes regarded as a northern extension of the Black Sea. The sea is bounded by Russia on the southeast and by Ukraine on the northwest.
The sea is largely affected by the inflow of the Don, Kuban, and other rivers, which bring sand, silt, and shells, which in turn form numerous bays, limans, and narrow spits. Because of these deposits, the sea bottom is relatively smooth and flat with the depth gradually increasing toward the middle. Also, due to the river inflow, water in the sea has low salinity and a high amount of biomass (such as green algae) that affects the water colour. Abundant plankton result in unusually high fish productivity. The sea shores and spits are low; they are rich in vegetation and bird colonies. The Sea of Azov is the shallowest sea in the world, with the depth varying between 0.9 and 14 metres (3 and 46 ft). There is a constant outflow of water from the Sea of Azov to the Black Sea.
Historically, the sea has had rich marine life, both in variety, with over 80 fish and 300 invertebrate species identified, and in numbers. Consequently, fishing has long been a major activity in the area. The annual catch of recent years was 300,000 tonnes, about half of which are valuable species (sturgeon, pike-perch, bream, sea-roach, etc.). This was partly due to extremely high biological productivity of the sea, which was stimulated by the strong supply of nutrients from numerous rivers feeding the sea, low water salinity, ample heating due to shallow waters and long vegetation period. However, diversity and numbers have been reduced by artificial reduction of river flow (construction of dams), over-fishing and water-intense large-scale cultivation of cotton, causing increasing levels of pollution. Fish hauls have rapidly decreased and in particular anchovy fisheries have collapsed.
The shores of the Sea of Azov contain numerous estuaries and marshes and are dominated by reeds, sedges, Typha and Sparganium. Typical submerged plants are Charales, pond weed, hornworts and water lilies. Also common is sacred lotus. The number of species is large; for example, the Belosaraysk and Berdyansk spits alone contain more than 200 each. Some spits are declared national nature reserves, such as Beglitsk,Belosaraysk, Krivaya and Berdyansk Spits.
Estuaries and spits of the sea are rich in birds, mostly waterfowl, such as wild geese, ducks and seagulls. Colonies of cormorants and pelicans are common. Also frequently observed are swans, herons, sandpipers and many birds of prey. Mammals include foxes, wild cats, hares, hedgehogs, weasels, martens and wild boar. Muskrats were introduced to the area in the early 20th century and are hunted for their fur.
For centuries, the Sea of Azov has been an important waterway for the transport of goods and passengers. The first modern ironworks in Imperial Russia were located upstream on the Kalmius River at Donetsk, originally named Hughesovka (Russian: Юзовка). It was also important for the transportation of iron ores from the mines of the Kerch peninsula to the processing plant of Azovstal in Mariupol (formerly Zhdanov), Ukraine; this activity stopped after the closure of the mines in the 1990s. Navigation increased after the construction in 1952 of the Volga–Don Canal which connected the Sea of Azov with the Volga River – the most important riverine transport route in the central Russia – thus connecting major cities such as Moscow, Volgograd and Astrakhan. Currently, the major ports are in Taganrog, Mariupol, Yeysk and Berdyansk.
Increasing navigation rates have resulted in more pollution and even in ecological disasters. On 11 November 2007, a strong storm resulted in the sinking of four ships in the Strait of Kerch, in the Russian Port of Kavkaz. The ships were the Russian bulk carriers Volnogorsk, Nakhichevan, Kovel and the Georgian Haji Izmail with a Turkish crew. Six other ships were driven from their anchors and stranded and two tankers were damaged (Volgoneft-139 and Volgoneft-123). As a result, about 1300 tons of fuel oil and about 6800 tons of sulfur entered the sea.
Another traditional activity in the sea is fishing. The Sea of Azov used to be the most productive fishing area in the Soviet Union: typical annual fish catches of 300,000 tonnes converted to 80 kg per hectare of surface. (The corresponding numbers are 2 kg in the Black Sea and 0.5 kilograms (1.1 lb) in the Mediterranean Sea.) The catch has decreased in the 21st century, with more emphasis now on fish farming, especially of sturgeon.
Traditionally much of the coastline has been a zone of health resorts.
The irrigation system of the Taman Peninsula, supplied by the extended delta of the Kuban River, is favorable for agriculture and the region is famous for its vines. The area of the Sivash lagoons and Arabat Spit was traditionally a centre of a salt-producing industry. The Arabat Spit alone produced about 24,000 tonnes/year in the 19th century.