Annual cycle of the Helmeted Honeyeater Lichenostomus melanops cassidix, a sedentary inhabitant of a predictable environment

Abstract

The annual cycle of breeding, moult and weight variation in the Helmeted HoneyeaterLichenostomus melanops cassidix, a sedentary bird of temperate southeast Australia, is documented. Breeding and moult were sequential unimodal annual events, whose timing was highly consistent between years. However, overlap of breeding and moult was frequent, and some individuals even commenced primary moult before laying their final clutch. The timing of the post‐juvenile moult was coincident with that of adults. Early‐hatched young moulted within a few months of hatching, but late‐hatched young deferred moult for a year. Helmeted Honeyeaters were heaviest in autumn and early winter, and lightest in spring and early summer, a cycle most consistent with the redirection of all available resources to reproduction. The long breeding season (seven‐and‐a‐half months) of the Helmeted Honeyeater, extensive overlap of breeding and moult, and other life‐history attributes including small clutch size, are more consistent with the described bio‐rhythmic patterns for birds in the humid tropics than the temperate zone. However, the Helmeted Honeyeater has a fairly rapid primary moult rate, unusual amongst species that overlap moult and breeding. This combination of attributes reflects the stable, somewhat seasonal environment occupied and the resource monopoly established by this tightly territorial subspecies. We speculate that extension of the breeding season, by overlapping breeding and moult, is one of the few options available to vary life‐history strategies amongst ‘old‐endemic’ Australian birds of the temperate zone.