The Caspian Kutum Rutilus kutum natural reproduction by shale technique in Nesarud and Kazemrud Rivers (Mazandaran province, Iran) was conducted in March 2017. A total of 353 and 865 spawners of male and female with the sex ratio of 5.1 to 1 were reintroduced to the rivers, respectively. The macrobenthic and fishes were sampled in three stations set downstream and upstream of shale cites monthly. In a review of two rivers, 8,000 macrobenthic were collected belonging to Oligochaeta, Diptera,

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... meroptera and Trichoptera. Biological indices (EPT and EPT / CHIR i ) showed the status of water quality in Kazemrud River was better than Nesarud and the water quality declined from upstream to downstream of the rivers. Hilsenhoff biological index (HFBI) showed the Nesarud River water quality was relatively as poor classes quality and in the upstream and downstream of the Kazemrud shale was appropriate. The number of Rutilus kutum larvae hatched in the Nesarud and Kazemrud rivers were 2000000 and 4200000 individuals larvae, respectively and the number of juveniles in the were 1100000 and 1300000 individuals.