Myzomela erythrocephala

Appearance

The red-headed myzomela is a distinctive small honeyeater with a compact body, short tail and relatively long down-curved bill. It averages 12 centimetres , with a wingspan of 17–19 centimetres and a weight of 8 grams . The birds exhibit sexual dimorphism, with males being slightly larger and much more brightly coloured than the females.

The adult male has a dark red head, neck, lower back and rump; the red is glossy, reflecting bright light. The rest of the upper body is a blackish-brown, and the upper breast and under-body a light brownish-grey. The bill is black or blackish-brown, and there is a distinct black loral stripe that extends to become a narrow eye ring. The adult female's head and neck are grey-brown with a pink-red tint to the forehead and chin. The rest of the female's upper body is grey-brown with darker shades on the wings and lighter shades on the breast and under-body. One study suggested a connection between the female's bill colour and breeding status, with birds that had a horn-coloured bill also having well-developed brood patches. Juveniles are similar to females though with an obvious pale yellow edge to the lower mandible. It seems that males keep their juvenile plumage for up to three months, and take a similar period to come into full colour. The subspecies are similar in appearance to the nominate race however ''M. e. dammermani'' is slightly smaller than the other subspecies and has darker upper parts and a broad black pectoral band and ''M. e. infuscata'' has red extending from the rump onto the back.

The red-headed myzomela has a range of contact calls and songs that are primarily metallic or scratchy. Its song is an abrupt ''tchwip-tchwip-tchwip-tchwip'' with a slightly softer ''swip-swip-swip-swip'' contact call and a scolding ''charrk-charrk''.

Distribution

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 Western Australia, 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, 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 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 cajeput . 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 Western Australia.

Status

''M. e. erythrocephala'' is listed as being of least concern by the IUCN, because the population is widespread, however ''Myzomela erythrocephala infuscata'' is listed as near threatened. The Australian population of this subspecies is confined to three small islands with a combined area of about 100 square kilometres . There is no immediate threat to the red-headed myzomela except the risk posed to low islands by rising sea levels, however it has been recommended that community-based ecotourism on the tropical coast be promoted, as it could lead to monitoring of sub-populations and habitat by visiting birdwatchers and local rangers.

Behavior

While the social organisation of the red-headed honeyeater is relatively unknown, it is reported as being usually solitary or found in pairs, though it has been described as forming loose associations with brown honeyeaters, and other mangrove-feeding birds such as the northern fantail and yellow white-eye. It is an inquisitive bird, and readily responds to pishing coming close to the caller to investigate the source of the sound and to warn off the intruder. It calls throughout the day when feeding, and males sing from exposed branches in the upper canopy of the food trees.

The red-headed myzomela actively defends food trees, engaging in aggressive bill-wiping both in response to a threat and after chasing intruders from a tree. It is very antagonistic even towards its own species; the males fight by grappling in mid-air and falling close to the ground before disengaging. It constantly chases brown honeyeaters through the canopy, though it has not been observed in grappling fights with other species.

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 Western Australia, 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, 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 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 cajeput . 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 Western Australia.

Reproduction

There are few scientific reports on the breeding behaviour of the red-headed myzomela, and little detail is available on the breeding season. A study of populations in the west Kimberley reported that the birds hold territories through much of the dry season and then disperse. The nest is built in the foliage of the mangroves, suspended by a rim from a small horizontal fork about 6–10 metres above the ground or water. The nest is small and cup-shaped, and built from small pieces of bark, leaves, plant fibre and sometimes seaweed, bound together with spider web and lined with finer material. It is, on average, 5.4 centimetres in diameter and 3.7 centimetres deep.

Measuring 16 by 12 millimetres , the eggs are oval, smooth and lustreless white, with small spots or blotches of red on the larger end. Clutch size is reported to be two or three eggs. While there is no reliable information on incubation and feeding, it is believed that both parents are active in caring for the young.

Food

The red-headed myzomela is arboreal, feeding at flowers and among the outer foliage in the crowns of mangroves and other flowering trees. It is very active when feeding, darting from flower to flower and sallying for insects. It probes flowers for nectar with its long curved bill, catches insects on the wing and gleans insects from leaves. It predominately feeds on mangrove species, and in north western Australia is the major pollinator of ''Bruguiera exaristata'', however it also feeds in paperbarks and other coastal forests and has been recorded feeding in cultivated bottlebrush and ''Grevillea'' in Darwin gardens.