Tilapia as exotic species

Throughout much of the tropics, tilapiine cichlids native to Africa and the Levant have been widely introduced into a variety of aquatic systems. In the U.S. States of Florida and Texas, tilapia were originally introduced out of an intention to curtail invasive plants. In an effort to meet the growing demand for tilapia, humans have farmed these fish in countries around the world. Capable of establishing themselves into new ponds and waterways, many tilapia have escaped aquaculture facilities across much of Asia, Africa and South America. In other cases, tilapia have been established into new aquatic habitats via aquarists or ornamental fish farmers.

Because tilapia are generally large, fast growing, breed rapidly, and can tolerate a wide variety of water conditions (even marine environments), tilapia establish themselves into new habitats rather quickly. In doing so, tilapia often out compete native fish, create turbidity in rivers by digging, and can reduce available sun light for aquatic plants. Tilapia greatly impact and alter local habitat. Many environmental problems wrought by tilapia have been observed in different locations, including Australia, the Philippines, and the United States.

During World War II Oreochromis mossambicus was introduced to Singapore by the Japanese, who had brought the fish from the island of Java. Hence the fishes' local names, Japanese fish and Java fish. Tilapia were once abundant in the fresh and brackish waters off the north coast of Singapore. Since the late 1980s however, populations of feral tilapia have declined. Recently introduced cichlid hybrids (red tilapia O. mossambicus x O. niloticus, possibly also O. honorum and O. aureus) have crossbred with populations of Oreochromis mossambicus, possibly contributing to the decline. Inter-species hybrids tend to produce fewer fry per brood than spawning by fishes of the same species. In addition, hybrids classified as O. niloticus may have inherited a diminished tolerance for saline conditions, thus restricting the environments in which tilapia can be found.

In Java or all Indonesian Archipelago this fish called "Mujair", that name get from name Mr. Moedjair ,a firsh fihshermen inventor this fish in mouth of Serang river in southern sea of Java island at year 1939.

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Wikipedia