Red-headed Myzomela - Distribution and Habitat

Distribution and Habitat

The Red-headed Myzomela in Australia is distributed across the tropical coastlines of Western Australia, the Northern Territory and Queensland. It inhabits coastal areas of the Kimberley and various offshore islands in W.A., and is similarly distributed in the Northern Territory, including Melville Island and the Sir Edward Pellew Group of Islands. It is widespread around the coast of the Gulf of Carpentaria and Cape York Peninsula. M. e. dammermani is found on the island of Sumba in the eastern Indonesian Lesser Sunda Islands, and M. e. infuscata at scattered sites in West Papua and in south Papua New Guinea.

Although the Red-headed Myzomela is widely distributed, it is not abundant within its range. The largest recorded population was 5.5 birds per hectare or 2.2 per acre at Palmerston in the Northern Territory. The peak abundance of the species in the mangroves around Darwin Harbour during the mid dry and early wet season coincided with the production of young and the flowering of Ceriops australis.

The species' movements are poorly understood, with them variously described as resident, nomadic or migratory. Population numbers have been reported as fluctuating in some areas with local movements possibly related to the flowering of preferred mangrove and Melaleuca food trees, and there is some indication that the birds can travel more widely. A single bird was recaptured after being banded nearly five years earlier, 27 kilometres (17 mi) from the original banding site, and the species' occupation of a large number of offshore islands suggests that the Red-Headed Honeyeater is effective at crossing distances over water.

The Red-headed Myzomela mostly inhabits mangroves in monsoonal coastal areas, especially thickets of Rhizophora, Bruguiera and Avicennia bordering islands or in river deltas, but it often also occurs in paperbark thickets fringing the mangroves such as those of the Cadjeput (Melaleuca leucadendra). It is a mangrove specialist, an adaptation that probably occurred as northern Australia became more arid and the bird populations became dependent on mangroves as other types of forest disappeared. The mangroves provide nectar and insects as well as shelter and nesting sites, and they supply the majority of the species' needs for most of the year.

In Australia, mangrove vegetation forms a narrow discontinuous strip along thousands of kilometres of coastline, accommodating birds specialized for the habitat. Eighty Mile Beach in Western Australia has no mangroves and no fringing Melaleuca forests, reducing its potential for successful colonization by nectarivores, and it marks the southern limit of the Red-headed Myzomela in W.A.