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Providing evidence to improve practice

Individual study: Painting wind turbine blades with thick black stripes increases their visibility to an American kestrel Falco sparvius in an ex situ experiment. Thin black stripes decrease visibility

Published source details

McIsaac H.P. (0) Raptor acuity and wind turbine blade conspicuity. Proceedings of National Avian-Wind Power Planning Meeting IV, 59-87.


This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.

Paint wind turbines to increase their visibility Bird Conservation

A randomised, controlled ex situ experiment on an American kestrel Falco sparverius (McIsaac 2001) found that it could discriminate between a control stimulus and an image of rotating wind turbine blades better if the blades were painted with two thick black bands running across the width of the blade (a visibility ratio of 2.4 in bright light, decreasing to 1.5 in low light, no difference in very low light). Blades with narrow black bands running across the width of the blade were less conspicuous in bright light (ratio of 0.1) and were indistinguishable in low light. A pattern of three stripes running the length of the blade were not significantly more or less conspicuous than plain white blades. Both the control (grey blade rotating in front of a grey background) and experimental stimuli rotated at 30 rpm.