Rattling Call of Crested Honey Buzzard Pernis ptilorhynchus

Abstract We describe, for the first time, the rattling call of the Crested Honey Buzzard Pernis ptilorhynchus. This was previously considered to be a unique vocalization of European Honey Buzzard Pernis apivorus; however, we detected this series of rapidly repeated notes given by an adult female, a second-year, a juvenile and a nestling Crested Honey Buzzard. The rattling calls appeared to be given at times of great excitement, such as to an approaching intruder, mate or parent at the nest, or to a familiar person who usually gave food in the case of captive individuals. The rattling call of an adult female Crested Honey Buzzard at the nest was at a frequency of 2.12 (s.d.±0.07) kHz, and lasted 141 (s.d.±18) ms, which was higher and longer than in European Honey Buzzard.