Mangrove honeyeater

Mangrove Honeyeaters are small to medium-sized nectar eating birds. Its plumage is olive-brown above, grading to greyish-brown on rump and uppertail-coverts, with fine dark streaking on top of head and hindneck. There is olive mottling on uppertail-coverts and broad black mask extending well down side of neck. A narrow yellow moustachial stripe exists that ends in small white tuft. It meets large greyish-white patch on lower side of neck and the tail and upperwing are olive-brown in color. The chin and throat are finely barred dark grey-brown and dull yellow in color. Its legs are colored in dark grey or bluish-grey. The back is dark-grey; only the flight feathers have yellowish-olive leading edges. The irises are dark blue-grey. The slightly down-curved bill is dark-grey. Male weighs between 23.9g to 33.1g and the female weighs between 22g to 30g.[2]

The mangrove honeyeater was previously placed in the genus Lichenostomus, but was moved to Gavicalis after a molecular phylogenetic analysis, published in 2011, showed that the original genus was polyphyletic.

Mangrove honeyeaters are found in Coastal Australia from Northeast Queensland near Townsville as well as in islands from Whitsunday Islands, Moreton Bay, and Northeast New South Wales. They are found mainly in Mangrove forests and woodlands fringing coasts, bays, estuaries and islands. They are less likely to be found in coastal shrubland, woodland or scrub (e.g. of Eucalyptus, Banksia, Melaleuca or combinations of these) near mangroves. The mangrove honeyeaters are a regular visitor to parks and gardens in some towns near mangroves.[3]

In Australia three species are largely restricted to mangroves. It is not uncommon to find ten or more species at a location in forests and coastal heathlands. Woodlands, mallee, and other semi-arid scrubs are also rich in species. Within forests and woodlands, most species occupy the canopy, with some of the more nectarivorous species feeding more in the shrub layer.[4]

Mangrove honeyeaters are monogamous, although polygamy or a mixed mating system is present in species with great sexual dimorphism. Honeyeaters lay 1-5 eggs (average 2). The eggs are white, pinkish colored, or buff with reddish-brown spots. Their incubation period is 12-17 days, while their nesting period lasts for 10-30 days.[5]

Mangrove honeyeaters usually feed on nectar and invertebrates, and sometimes fruit. The invertebrates they eat include insects, marine snails, and crab. Honeyeaters forage mainly in mangroves (Aegiceras, Rhizophora), among outer foliage, in flowers, trees, and shrubs.[6] Other sweet food sources include honeydew from bugs (Hemiptera), manna (sugary exudate from damaged foliage), and lerp (the sugary coating on scale insects of the family Psyllidae). Honeyeaters also consume sap exuding from scars on branches caused by gliding possums.[7]

The mangrove honeyeater is not globally threatened. They have restricted range and the population size is not quantified, but is not considered vulnerable due to the size of its range. The range is thought to have expanded over the last 50 years, with first records if the bird at Yamba in 1947, and some following records farther south.[10]