Interesting Reading  - a study done on the effects of Helicopter noise on the endangered Birds of Dassen Island. One of the best-studied groups of birds for the impact of aircraft is penguins. Some species of penguins are prone to panic responses to helicopters (e.g. Wilson et al. 1991, Cooper et al. 1994, Giese & Riddle 1999), occasionally with catastrophic results (Rounsevell & Binns 1991). Most catastrophic events happen among dense groups of penguins, where even one bird panicking can set off a chain reaction throughout the group.  Source: http://adu.org.za/pdf/Nansikombi_Juliet_2004_MSc_CB_thesis.pdf Image source: Wikipedia - Michael John Nicoll - Nicoll, M. J. (1908) Three Voyages of a Naturalist : Being an Account of Many Little-Known Islands in Three Oceans Visited by the 'Valhalla' R. Y, S., London : Whitherby & Co.