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Providing evidence to improve practice

Action: Thicken earth wire to reduce incidental bird mortality Bird Conservation

Key messages

Read our guidance on Key messages before continuing

A literature review found no evidence that thickening the earth wire had any impact on collision mortality of cranes Grus spp.


Supporting evidence from individual studies


A literature review (Jenkins et al. 2010) describes how a paired site study in Colorado, USA (Brown et al. 1987), found that replacing 50% of the earth wire from 3.2 km of 115 kV wire with an earth wire three times thicker than normal had no effect on crane Grus spp. collision mortality compared to the span with a normal thickness earth wire.

Additional reference

Brown, W. M., Drewien, R. C. & Bizeau, E. G. (1987) Mortality of cranes and waterfowl from powerline collisions in the San Luis Valley, Colorado. 128–136 Proceedings of the crane workshop, 1985 Platte River Whooping Crane Maintenance Trust, Grand Island, Nebraska


Referenced papers

Please cite as:

Williams, D.R., Child, M.F., Dicks, L.V., Ockendon, N., Pople, R.G., Showler, D.A., Walsh, J.C., zu Ermgassen, E.K.H.J. & Sutherland, W.J. (2019) Bird Conservation. Pages 141-290 in: W.J. Sutherland, L.V. Dicks, N. Ockendon, S.O. Petrovan & R.K. Smith (eds) What Works in Conservation 2019. Open Book Publishers, Cambridge, UK.