Investigation of distribution and frequency of Prussian carp (Carassius gibelio) in Anzali Wetland

Indigenous and exotic fish species are of great importance in biological studies for a variety of reasons, including biodiversity, water indicators, and finally as a white in human food supply. A few fish fauna studies on Anzali lagoon have been done in previous years. The study of fish communities in Anzali wetland during 2013 to 2014 was done by sampling 14 stations by electroshock and cast-net in which 6757 fish specimens were caught, weighed and then 2763 of them were bioassay. Three species of non-native fish, prussian carp, Gambusia and sharp belly with 63.6%, had the highest frequency among the fish caught. Carassius gibelio was caught in all stations and in all seasons. The sex ratio (males: females) in C. gibelio was 1:11 and the age of the specimens was between 1 to 5 years. The average of total length and body weight was determined 126 mm and 46 g, respectively. The maximum total length was 315 mm with 621 g.