Oriental Darter Anhinga melanogaster Scientific name definitions

85–97 cm; 1058–1815 g; wingspan 114–128 cm; bill 71–87 mm. Scapulars elongated and lanceolate ; bare part colours variable. Juvenile  similar to female, but white and black areas generally replaced by buff and brown. Sexual dimorphism in plumage less evident than in other darters.

Often considered conspecific with A. rufa and A. novaehollandiae. Less sexually dimorphic in plumage than either of these species and differs in plumage features (1 Schodde, R., Kirwan, G.M. and Porter, R.F. (2012). Morphological differentiation among the darters (Anhinga). Bull. Brit. Orn. Club 132(4): 283–294. Close ); these differences include having more a conspicuous white line around the eye; the head and hind-neck are speckled dusky, straw and fawn; the pale cheek stripe is narrower and extends further, halfway down the neck; male throat is extensively white spotted black; male neck is midbrown spotted dusky, not black or rufous; dorsal shaft streaks are bright whitish grey, brighter than in the other two species. Monotypic.

Pakistan (mainly Indus Valley), India and Sri Lanka E to mainland SE Asia, Greater Sundas, Philippines, Sulawesi and W Lesser Sundas (Sumbawa).

Mainly still, shallow inland waters , such as freshwater or alkaline lakes, slow flowing rivers, swamps and reservoirs; less often estuaries or tidal inlets and coastal zones with mangroves and lagoons. Requires scattered emergent trees, forested margins or islets with dense vegetation.

Generally sedentary, with sporadic movements usually related to drought conditions.

Mainly fish ; prey species vary with locality. Also takes amphibians, water snakes, terrapins and aquatic invertebrates, including insects, crustaceans and molluscs. Prey speared under water , without active pursuit.

Usually silent, except in vicinity of nest. Main call is a lengthy, accelerating and swelling sequence of ratchety clicks, dying off towards the end (2 Rasmussen, P. C., and J. C. Anderton (2005). Birds of South Asia: the Ripley Guide. Lynx Edicions, Barcelona, Spain. Close ).

Seasonal in some areas, at any time of year in others. Usually colonial, often with cormorants or Ciconiiformes. Nest is platform of sticks and sometimes reeds, often c. 2 m above water. 2–6 eggs, usually 3–5; incubation 26–30 days; chicks naked, grow whitish down; fledging c. 7 weeks. Sexual maturity probably only after at least 2 years. Known to have lived over 9 years in wild, and over 16 in captivity.

Not globally threatened. Currently considered Near Threatened, with a global population of 30,000 individuals. Generally uncommon and declining throughout Asia, due to habitat loss, hunting and pollution. Regional occurrence, according to Birdlife International, as follows. Fairly widespread in Pakistan and India : where locally common in Assam. Also common in the dry lowlands of Sri Lanka. An uncommon resident and non-breeding visitor to Nepal. Locally resident in northern and coastal Bangladesh. Formerly widespread in Burma but now scarce to locally fairly common in south and of uncertain status elsewhere. Formerly widespread in Thailand but now a rare although increasingly frequent visitor. Similarly formerly widespread in Laos and Vietnam but now rare or extinct as a breeding species, although non-breeders are increasingly frequent. Formerly abundant in Cambodia, where flocks of several thousand were reported on the Mekong in the early 1960s; still breeds there especially at Tonle Sap Lake, where the largest colony at Prek Toal has grown from 241 nests in 2002 to 6000–7000 nests in 2011; this colony be may the source of increasing reports in adjacent countries. Vagrant to peninsular Malaysia but widespread and locally common as a breeding species in Borneo (Sabah, Sarawak, Brunei and Kalimantan); In Indonesia also locally common in Java and Sulawesi, vagrant elsewhere. An uncommon resident in Timor-Leste.