Investigation of Habitat Suitability of Persian sturgeon (Acipenser persicus Borodin, 1897) in the southern of Caspian Sea basin using Multivariate Analyses

For protection of aquatic ecosystems and fish, enough knowledge on habitat requirements of aquatic species plays an important role. Therefore, the purpose of this study was investigating Habitat Suitability of Persian sturgeon (Acipenser persicus Borodin, 1897) in the southern of Caspian Sea. Relationships among important factors of effective at distribution this species (benthos, temperature, salinity, O2, %TOM, %Silt-clay and depth) with its catch were evaluated during April 2010 to December 2016. This study focuses on the number of 3138 specimens were caught by fixed gill net and beach seine. Also for calculate environmental factors used from data of satellite images, sampling and past studies. For survey this relationship, used Redundancy Analysis (RDA) method using CANOCO software. Results showed that temperature, %Silt-clay, benthos, salinity and %TOM were important factors at distribution this species. But O2 and depth factors don’t have a significant effect on the distribution of Acipenser persicus. The mostly-selected environmental factors of this species were Optimum temperature ranging from 12 to 25˚C, its favoritesubstrate gravel, sand and silt, salinity ranging from 11 to 14 ppt, %TOM ranging from 2.2 to 3.3. Result this study showed that is high correlation among the catch data of Acipenser persicus,environmental factors and benthos. Therefore, awareness of the relationship between environmental factors and the catch data of Acipenser persicus will help these findings to be used in management, conservation programs and the prevention of the extinction of this species.