None-Indigenous Fishes of Alma-Gol, Adji-Gol and Ala-Gol Wetlands (Golestan Province); mplications for Conservation and Management Programs of Wetlands

The study was conducted to explore fish species composition of the international wetlands of Golestan province, which represent a series of the small and rather isolated freshwater lakes during September 2000 to August 2002. The results revealed that non-indigenous fish species are dominant in the wetlands. Of 10 sampled species, four including Sharp Belly Hemiculter leucisculus, Silevr Crucian Carp Carassius auratus, Top mouth Gudgeon Pseudorasbora parva, Mosquito fish Gambusia holbrooki, were non-indigenous. Alma- Gol and Ala-Gol contained 89.80% and 79.57% (of total frequency of fishes) of none-indigenous species respectively, indicating decreasing of native fish fauna. The most frequent noneindigenous species were H. leucisculus in Alma- Gol (58%), C. auratus in Ala-Gol (77.6%) and H. leucisculus in Adji-Gol (16.82%). As numerical abundance, two none-indigenous species H. leucisculus and C. auratus had the highest biomass in the Alma-Gol and Ala-Gol respectively. This situation highlights the importance of conservation and protection measures. Therefore, if greater emphasis is not placed on the conservation of native fishes with no direct economic values, these species could face continuous decline or might be completely lost.