A study of Resource Partitioning Within the Helmeted Honeyeater Lichenostomus melanops cassidix During the Non-breeding Season

Abstract

Intraspecific variation in resource partitioning was evaluated in the Helmeted Honeyeater Lichenostomus melanops cassidix according to age, sex and breeding status during the 1994 non-breeding season. The home ranges of males and females within a breeding pair were highly over-lapping, of similar size (males: X − = 0.32 ± 0.07 ha; females: X− = 0.26 ± 0.04 ha) and did not differ significantly in vegetational omposition. Breeding adults and their juvenile off-spring also had similar-sized, highly overlapping home ranges. For one juvenile the degree of overlap decreased markedly as the bird matured. Non-breeding adults tended to occupy different vegetation communities to those inhabited by breeding adults. Male breeding adults spent significantly more time in the canopy stratum than females, who were observed more frequently in the lower strata. Both juveniles and non-breeding adults spent less time in the canopy than breeding adults. Analysis of activity budgets did not reveal specialised foraging behaviour according to height in the vegetation, or seasonal change from autumn to winter. Male and female Helmeted Honeyeaters showed similar levels of aggression when present in the canopy region. The distribution of manna points was random at Green site, but occurred in areas with little tea-tree understorey at Mauve site.