Ecology of Honeyeaters (Meliphagidae) in Western Australian Eucalypt Woodlands I: Resource Allocation Among Species in the Great Western Woodland During Spring

Abstract

Nectar-feeding birds are commonly the most abundant birds in Australian eucalypt forests and woodlands, where they play a key role as pollinators of native plants. Among the nectar-feeders, honeyeaters (Meliphagidae) are particularly aggressive and may exclude other birds from the habitats they occupy thereby affecting the composition of avian communities and the distribution of species on a landscape scale. Such behaviour has cascading effects on ecosystems, changing the abundances and kinds of planteating arthropods. A comprehensive knowledge of the ecology of honeyeaters is therefore basic to the conservation management of Australia's natural environments. In this paper, we describe the foraging ecology of honeyeaters in the Great Western Woodland (GWW) during the spring, comparing the use of resources between species and locations. Species of honeyeaters in the GWW differ morphologically, and in social and dispersive behaviour, but aggregate in multi-species flocks on blossoming eucalypts (Eucalyptus spp.), the main source of nectar. There are differences among the species of honeyeaters in the eucalypts frequented as nectar sources, with these differences reflecting differences among species in habitat. Species also differ in foraging manoeuvres (the way food is taken), substrates, and heights, as well as the plant species visited when feeding on foods other than nectar (e.g., lerp, arthropods, and fruit). The use of substrates and foraging manoeuvres differed between locations. Differences in foraging ecology between locations were primarily related to differences in flowering phenology and vegetation structure (e.g., height, type of bark) and floristics, which in turn affected the food resources available to honeyeaters. Our observations support arguments that the long-term conservation of nectar-feeders cannot be achieved by relying on a fragmented system of widely dispersed conservation reserves. This is especially true in an era of accelerated climate change. Instead, a landscape scale, if not a continental scale, approach to ecosystem conservation that emphasizes habitat connectivity is required.

The habitat suitability of Timor friarbird (Philemon inornatus) in Western Timor Island, Indonesia

“…The specialist has been supported by its special characteristics in the form of a long and sturdy beak to pick up nectar on a large or deep flower crown like Bombax ceiba and insects on the bark of trees. Honeyeaters select flowers by size and sturdiness of available perches such as Eucalyptus spp., feed on large inflorescences (Recher and Davis 2011), which flowered more abundantly, had cup-shaped flowers (Recher et al 2016). This is in line with Scoble and Clarke (2006), that nectarivorous birds (family Meliphagidae) prefer flowers that contain large amounts of nectar.…”

Pollination strategies are exceptionally complex in southwestern Australia – a globally significant ancient biodiversity hotspot

“…The most reported is the New Holland honeyeater (Phylidonyris novae-hollandiae) with 142 plant species. Honeyeaters have diverse foraging preferences and diets, and they can feed primarily on nectar or other foods depending on species, habitats and timing (Collins and Briffa 1982;Recher and Davis 2011;Low 2014) Nectar-feeding birds can be nomadic to exploit unreliable resources in dry areas (Main 1981). Some bird-flower associations are less specialised in Australia, because birds such as silvereyes and some parrots are casual pollinators and other birds that visit flowers may be feeding primarily on insects (Anderson et al 2016).…”

Global change and plant–pollinator communities in Mediterranean biomes

“…among butterfly groups in renosterveld scrublands, Cape Region) (Topp et al, 2022). Regarding bird pollinators, research in the Cape Region and Australia has shown that non‐migratory, exclusive nectar consumers, which normally are active throughout the year in the same area, can suffer severe impacts if the density of post‐fire intact patches of nectar‐providing bushes falls below certain thresholds (Geerts et al, 2020; Recher & Davis Jr., 2011). The differential responses of pollinator groups to fire traits suggest a need for caution in invoking the intermediate disturbance hypothesis, especially when natural fire patterns are altered (Box 3).…”