The Indian pond heron or paddybird (Ardeola grayii ) is a small heron. It is of Old World origins, breeding in southern Iran and east to the Indian subcontinent, Burma, and Sri Lanka. They are widespread and common but can be easily missed when they stalk prey at the edge of small water-bodies or even when they roost close to human habitations. They are however distinctive when they take off with bright white wings flashing in contrast to the cryptic streaked olive and brown colours of the body. Their camouflage is so excellent that they can be approached closely before they take to flight, a behaviour which has resulted in folk names and beliefs that the birds are short-sighted or blind.
The habit of standing still and flushing only at the last moment has led to widespread folk beliefs that they are semi-blind and their name in many languages includes such suggestions. In Sri Lanka the bird is called kana koka which translates as "half-blind heron" in the Sinhala language. The Hindustani phrase "bagla bhagat" has been used to describe a "wolf in sheep's clothing" or a hypocrite appearing like a meditating saint and occurs in a Marathi proverb. The paddy-bird also appears as a character in the Hitopadesha where, in one story, it takes injury to itself to save a king. The bird was noted by Anglo-Indian naturalist-writers for the surprising transformation in colours. Phil Robinson described the bird as one that sits all dingy gray and flies all white. It is said to have been eaten by many in India in former times.
During the height of the plume trade, feathers were collected from the "paddy bird" and exported to Britain.
They appear stocky with a short neck, short thick bill and buff-brown back. In summer, adults have long neck feathers. Its appearance is transformed from their dull colours when they take to flight, when the white of the wings makes them very prominent. It is very similar to the squacco heron, Ardeola ralloides, but is darker-backed. To the east of its range, it is replaced by the Chinese pond heron, Ardeola bacchus.
During the breeding season, there are records of individuals with red legs. The numbers do not suggest that this is a normal change for adults during the breeding season and some have suggested the possibility of it being genetic variants.
Erythristic plumage has been noted. The race phillipsi has been suggested for the populations found in the Maldives, however this is not always recognized. It forms a superspecies with the closely related Chinese pond heron, Javan pond heron and the Madagascar pond heron.
They are usually silent but may make a harsh croak in alarm when flushed or near their nests.
This bird was first described by Colonel W. H. Sykes in 1832 and given its scientific name in honour of John Edward Gray. Karyology studies indicate that pond herons have 68 chromosomes (2N).
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