Mitigation of bird collisions with transmission lines through groundwire marking

  • Published source details Alonso J.C., Alonso J.A. & Muñoz-Pulido R. (1994) Mitigation of bird collisions with transmission lines through groundwire marking. Biological Conservation, 67, 129-134.


This study is summarised as evidence for the following.

Action Category

Mark power lines to reduce incidental bird mortality

Action Link
Bird Conservation
  1. Mark power lines to reduce incidental bird mortality

    A controlled before-and-after trial in the winters of 1989-90 and 1990-1 in mixed woodland and farmland in Extremadura, Spain (Alonso et al. 1994), found there were fewer collisions and fewer birds flying between lines following the marking of four sections of line (60% reduction in fatalities: 45 vs. 18; 61% decrease in birds flying between lines: 357 birds/day vs. 124 birds/day). There were no such decreases at unmarked spans of wire (19 vs. 15 fatalities). Markers were coloured PVC spirals (1 m long, 30 cm in diameter) attached every 10m.


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