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Providing evidence to improve practice

Individual study: Experimental test of the effectiveness of various measures to prevent the collision of birds with windows near Cobden, Illinois, USA

Published source details

Klem D. Jr. (1990) Collisions between birds and windows: mortality and prevention. Journal of Field Ornithology, 61, 120-128


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

Mark or tint windows to reduce collision mortality Bird Conservation

A randomised, replicated and controlled study over 52 days in Illinois, USA (Klem 1990), found that marking windows in various ways did not reduce the number of birds colliding with the windows, compared to an unmarked control window. Similarly, a randomised, repeated and controlled choice experiment in a flight cage found that dark-eyed juncos Junco hyemalis did not consistently avoid windows marked with wind chimes, silhouettes of falcons, plants, stickers of eyes or model owls. However, birds tended to avoid windows that were completely covered by white cloth, or covered by closely spaced cloth strips and meshes. Widely spaced cloth strips and flashing lights partially increased avoidance.