The visual fields of vultures contain a small binocular region and large blind areas above, below and behind the head. Head positions typically adopted by foraging vultures suggest that these visual fields provide comprehensive visual coverage of the ground below, prohibit the eyes from imaging the sun and provide extensive visual coverage laterally. However, vultures will often be blind in the direction of travel. We conclude that by erecting structures such as wind turbines, which extend into open airspace, humans have provided a perceptual challenge that the vision of foraging vultures cannot overcome.
Graham R. Martin, School of Biosciences, University of Birmingham, U.K.
Steven J. Portugal, Structure and Motion Laboratory, The Royal Veterinary College, North Mymms, Hatfield, Hertfordshire, U.K.
Campbell P. Murn, Hawk Conservancy Trust, Sarson Lane, Weyhill, Andover, Hampshire, U.K.
Ibis: The International Journal of Avian Science
Volume 154, Issue 3, July 2012, Pages 626-631
doi: 10.1111/j.1474-919X.2012.01227.x 
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