Australian White Ibis
Threskiornis molucca
The Australian white ibis is a fairly large ibis species, around 65–75 cm (26–30 in) long and has a bald black head and neck and a long black downcurved beak, measuring over 16.7 cm (6.6 in) in the male, and under in the female. There is some sexual dimorphism in size, as the slightly heavier male weighs 1.7–2.5 kg (3.7–5.5 lb) compared to the 1.4–1.9 kg (3.1–4.2 lb) female. As a comparison, the American white ibis generally attains 1 kg (2.2 lb) in weight. The body plumage is white, although it may become brown-stained. Inner secondary plumes are displayed as lacy black "tail" feathers.
ID text from Wikipedia, CC BY-SA 4.0
Black-headed Ibis
Threskiornis melanocephalus
The black-headed ibis is one of several large waterbird species in south and south-east Asia, with adults measuring 65–76 cm in length. The white plumage is starkly contrasted against a conspicuous naked black neck and head, and black down-curved beak. Tails of adults bear light grey ornamental feathers that turn jet black during the breeding season. During the breeding season, bare patches under the wing turn blood-red. The head of some breeding adults gain a blueish tinge, or very rarely have a pink or bright red patch behind the neck.
ID text from Wikipedia, CC BY-SA 4.0
Where you might meet both
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