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Sri Lanka is a tropical island situated close to the southern tip of India. It is situated in the middle of Indian Ocean. Because of being an island, Sri Lanka also has marine and brackish water fish, as well as freshwater fish. Brackish water is the water that has more salinity than fresh water, but not as much as seawater. It may result from mixing of seawater with fresh water, as in estuaries, or it may occur in brackish fossil aquifers. Brackish water condition commonly occurs when fresh water meets seawater. Brackish water habitats worldwide are estuaries, where a river meets the sea and mangroves, brackish marshes and brackish lakes and seas. Sometimes, marine and Brackish water species enter and remain in fresh water. Such fish are enable to control the osmotic pressures and hypertonic and hypotonic concentrations for survive. Since Sri Lanka was ruled by Portuguese, Dutch, and British, they began introducing a number of exotic species including mammals, plant, birds and fish. The introduction of the fish has led to serious ecological damage, because they always damage the internal diversity and extinction of endemic fauna as well. Most of these exotic species brought for commercial purposes, such as seafood and aquarium fish. But releasing them to natural ecosystems will result many harms. Exotic fish in Sri Lanka is become now serious, due to invasiveness. There are 8 known marine and brackish water fish that enter freshwater ecosystems in and around Sri Lanka. There are 24 introduced fish species which inhabit all freshwater, brackish water and marine waters. ==Brackish water List== Class: Actinopterygii 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「List of brackishwater and Introduced fish of Sri Lanka」の詳細全文を読む スポンサード リンク
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