Effects of helicopter operations on emperor penguin chicks

The flights were conducted on the same day but under different wind conditions: a morning flight with a 10 kt (18 km.hr-1) katabatic blowing perpendicular to the direction of helicopter travel and an afternoon flight with virtually no wind.

Background noise levels recorded in the morning, before the helicopter flight, were significantly higher than in the afternoon, but these differences were not detectable when the helicopter was overhead. There were also no significant differences in the way chicks responded to helicopters between the morning and afternoon flight. All chicks became more vigilant when the helicopter approached and 69% either walked or ran, generally moving less than 10 m toward other chicks (i.e. not scattering).