On the 199 km surveyed, 123 birds of at least 18 species were found.
Jessica M Shaw1*, Andrew R Jenkins1, Peter G Ryan1 and Jon J Smallie2 1 DST/NRF Centre of Excellence at the Percy FitzPatrick Institute, University of Cape Town, Private Bag X3, Rondebosch 7701, South Africa 2 Wildlife and Energy Programme, Endangered Wildlife Trust, Private Bag X11, Parkview 2122, South Africa * Corresponding author, e-mail: email@example.com
Avian mortality on power lines in South Africa is currently recorded on the Central Incident Register (CIR), which is a collation of incidentally reported cases. The true scale of the problem is unknown, so we report here on a survey of representative power lines in the Overberg region of the Western Cape. On the 199 km surveyed, 123 birds of at least 18 species were found.
Collisions were more common than electrocutions, apparently killing 88% of the birds found on distribution lines. Large terrestrial birds were the most numerous victims, with large numbers of Blue Cranes Anthropoides paradiseus and Denham’s Bustards Neotis denhami killed. In comparison with mortality rates from the CIR, we estimate that only 2.6% of power-line mortalities are reported, emphasising the importance of systematic surveys in quantifying mortality and directing mitigation.
Our survey highlights the general hazard that power lines pose to avifauna, and the urgent need for further research into the population impacts of the high incidence of collisions.