An assessment of the potential effect of oil-and-gas 6 – 10 kV overhead power lines on bird mortality in the western Orenburg Region steppe

This paper calculates a possible damage to avifauna during the oil and gas production in the western Orenburg Region steppe. Based on field data on bird mortality by electrocution at 6 – 10 kV overhead power lines in the study area (3.22 individuals/km), we calculated possible values of bird mortality within the model site of oil and gas fields with a broad road and electrical network. The total estimated number of dead birds reached 432.64 individuals at the power lines of the model site with a total length of 134.36 km, and the estimated amount of damage was 991560 rubles. Birds pertaining to the Corvids, Accipitrids, and Falcons perished most frequently at unsafe power lines. When oil and gas fields are located near specially protected natural areas or in the Russian-Kazakh border zone, the estimates of bird deaths at unsafe power lines are supposed to be closer to actual values.