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Anzali Wetland is one of the most important wetland in southern Caspian Sea due to ecological aspects, commercial values, tourism and genetic diversity. It is a suitable habitat for migration and spawning of many Caspian Sea fish species. The present study was conducted in 4 main wetland basins including Siahkeshim, Sheijan, Sorkhankol and Abkenar; the estuary region; and 11 incoming rivers including Chafroud, Bahambar, Morghak, Khalkaei, Palangvar, Masoolehroodkhan, Pasikhan, Siahdarvishan, Pirbazar, Tashrud and Shijanrud. The identification, dispersion, abundance and IUCN category of fish species were investigated in Anzali Wetalnd during 2016-2017. The electrofishing equipment was used for sampling and the biological characteristic of fishes was studied including length and weight frequency, age classes and sex ratio. The result showed that 57 fish species belong to 15 families exist in Anzali Wetland. The highest species diversity belong to Cyprinidae family with 26 species, followed by Gobiidae, Clupeidae and Percidae families with 9, 4 and 3 species respectively. In the main basins and in the estuary area were identified 43 and 27 species, respectively while from these two areas were totally identified about 52 species. 38 species of fish were sampled in the rivers that Siahdarvishan and Morghak with 34 and 11 species had the most and the least species, respectively. Among identified fishes, 31 species were freshwater fish, 9 species were migrate in fresh water (anadromous fish), 12 species were estuarine species and some species were multi-habitat. The species belong to 13 exotic and 44 native or endemic species. Alburnus chalcoides and Carassius gibelio were highly distributed in the all basins and rivers. Gambusia holbrooki with 22.8%, Carassius gibelio with 19.7%, Hemiculter leucisculus with 12.1%, and Blicca bjoerkna with 10.1% were abundant in the main basins of Anazli Wetland. Alburnoides samiii, Capoeta razii and Ponticola iranicus had comprised 24.8%, 17.1% and 16.6% of frequencies among 38 identified fish species in the rivers. Studying of growth showed that more than 60% of species had isometric pattern and others had the negative or positive allometric patterns. The average of condition factor varied between 1.1 and 1.9. The IUCN category of commercial fishes was concluded for Blicca bjoerkna and Scardinius erythrophthalmus as without problem (least concern) and 5 species: Cyprinus carpio, Rutilus lacustris, Esox Lucius, Perca fluviatilis and Sander lucioperca as vulnerable category. Three commercial species Abramis brama, Luciobarbus capito and Tinca tinca were in endangered category and 2 species, Leuciscus aspius and Silurus glanis were in critically endangered category and two last groups need to more attention and special conservation program. Keywords: Anzali Wetland, Fish, Distribution, Abundance, Ecology.
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