Ecology of Honeyeaters (Meliphagidae) in Western Australian Eucalypt Woodlands II. Yellow-plumed Honeyeater Lichenostomus (Ptilotula) ornatus

Abstract

The Yellow-plumed Honeyeater Lichenostomus (Ptilotula) ornatus is a short-billed honeyeater which has declined in abundance over its range in Western Australia (WA), but remains abundant in the Great Western Woodland (GWW) where this study was conducted. It is also found in southeastern Australia where it occurs mostly in mallee woodlands. Yellow-plumed Honeyeaters form colonies from which they exclude small honeyeaters, canopy insectivores, and lerp-feeders; colonies persist for years. Colonies occurred in habitats dominated by different species of eucalypts (Eucalyptus spp), but were structurally similar, with trees of similar size forming a dense canopy, and lacking a shrub layer. Yellow-plumed Honeyeaters rely on lerp and honeydew for energy and take arthropods within the colony by gleaning and probing from eucalypts, and opportunistic hawking. Foliage is the most common foraging substrate, but they also probe under bark of live branches and trunks. Yellow-plumed Honeyeaters move between patches of nectar-rich flowers outside the colonies, aggregating where eucalypt blossom is abundant. Such movements can be described as locally nomadic and there was no evidence in the GWW of migration or regional scale movements. The proportion of nectar and non-nectar foraging did not differ between years or localities, with half of foraging observations being of nectar-feeding. Yellow-plumed Honeyeaters are sensitive to the effects of drought, with less nesting during dry seasons, and colonies abandoning less productive habitats. Nests were spaced over a wide height range, but most were in the lower canopy of eucalypts. Nesting was not synchronous. Their decline can be attributed to the fragmentation and clearing of the most productive habitats in WA for agriculture and urban expansion. Extensive areas of productive forest and woodlands are required to maintain colonies. As a result, Yellow-plumed Honeyeaters are vulnerable to land-clearing and climate change and should be listed as threatened. Currently they are listed as a species of ‘Least Concern’. Conservation of Yellow-plumed Honeyeaters and associated species will only be achieved through protection of extensive areas and corridors of intact forest and woodland, such as the Great Western Woodland in WA.