Effectiveness of Marking Powerlines to Reduce Sandhill Crane Collisions

  • Published source details Morkill A.E. & Anderson S.H. (1991) Effectiveness of Marking Powerlines to Reduce Sandhill Crane Collisions. Wildlife Society Bulletin, 19, 442-449.


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 replicated, paired sites study (Morkill & Anderson 1991) in south-central Nebraska, USA, between 1988-1990, found that marking the static wire of nine spans of high-voltage transmission wire reduced collision mortality in sandhill cranes Grus canadensis by 66% compared with unmarked spans (11 fatalities vs. 25). Crane flocks were also more likely to increase altitude (454 flocks vs. 397) or change direction gradually (114 vs. 92) when flying close to marked spans, but were less likely to react quickly (and potentially dangerously) to marked spans (19 vs. 36) or show no reaction (1,200 vs. 768). Experimental spans were 1-2.5 km in length and marked with yellow aviation balls (30 cm in diameter with a vertical black stripe) at 100m intervals, staggered to appear more closely spaced.


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