Comparison of Vocalisations of Australian Falcons and Elanine Kites

Abstract

Vocalisations were recorded from seven species of Australian raptors; five species of falcons: the Peregrine Falcon Falco peregrinus, Black Falcon F. subniger, Australian Hobby F. longipennis, Australian (Nankeen) Kestrel F. cenchroides and Brown Falcon F. berigora, and two species of Elanus kites, the Black-shouldered Kite E. notatus and Letter-winged Kite E. scriptus. Each species produced structurally distinct vocalisations in different behavioural contexts. Calls were generally harsh or harmonic, of wide frequency range, with the greatest acoustic energy between 1.1-6 kHz. All species produced vocalisations when disturbed or physically restrained. The Elanus kites have very similar vocalisations, showing striking similarities in the structure of their distress calls.