Breeding Behaviour and Diet of the Square-tailed Kite Lophoictinia isura in South-eastern Queensland

Abstract

A pair of Square-tailed Kites Lophoictinia isura and their offspring were observed in coastal southern Queensland through incubation, nestling and post-fledging periods (total 196 hours over 103 days, 3 September to 14 December 1998). Behaviour patterns, sex roles, voice, and growth and development of the young are described. Previously undocumented behaviour in the wild, e.g. sunning and sibling rivalry, is described. The male shared incubation, but little of the brooding; the nestling period lasted 55-59 days. Prey delivery rates during each phase of breeding were: incubation, 0.2 item/hr; nestling period, 0.4-0.5/hr (highest in the first half); post-fledging, 0.6/hr (of which half was contributed by the female). The Kites' diet, by number consisted of small birds (mostly nestlings or fledglings, 43%), birds' eggs (15%), and insects(mostly ants and beetles, 42%; n = 31 pellets, of which all contained feathers and/or eggshell). One juvenile Kite fledged successfully, spending only 5-7 days in the immediate nest area; the other fledged in poor condition and probably would have died without human intervention.