The Yellow-billed Babbler also called the White-headed Babbler (Turdoides affinis) is an Old World babbler endemic to southern India and Sri Lanka. The Old World babblers are a large family of Old World passerine birds characterized by soft fluffy plumage. These are birds of tropical areas, with the greatest variety in southeast Asia.
The Yellow-billed Babbler is a common resident breeding bird in Sri Lanka and southern India. Its habitat is scrub, cultivation and garden land. This species, like most babblers, is not migratory, and has short rounded wings and a weak flight and is usually seen calling and foraging in groups.
These birds have grey brown upper parts, grey throat and breast with some mottling, and a pale buff belly. The head and nape are grey. The Sri Lankan form T. a. taprobanus is drab pale grey. Nominate race of southern India has whitish crown and nape with a darker mantle. The rump is paler and the tail has a broad dark tip. Birds in the extreme south of India are very similar to the Sri Lankan subspecies. The eye is bluish white. The Indian form is more heavily streaked on the throat and breast. The Sri Lankan subspecies resembles the Jungle Babbler, Turdoides striatus, although that species does not occur on the island.
The Yellow-billed Babbler lives in flocks of seven to ten or more. It is a noisy bird, and the presence of a flock may generally be known at some distance by the continual chattering, squeaking and chirping produced by its members. One member often perches high and acts as a sentinel while the remaining members of the flock forage. They feeds mainly on insects, but also eat fruit and human food scrap.
Birds wake up before dawn around 6 AM and begin foraging. They are relatively inactive in the hot hours of the day from 1330 to 1630. They assemble in groups around 1900 hrs and preen themselves before going to roost. Members of a group roost next to each other with some juveniles wedging themselves in the middle of the group. When foraging the sentinel bird calls with wing fluttering and hopping. Allopreening is a common activity and members may beg for food from other members.
A study in the Sivakasi plains noted that the birds had a home range of 0.4 sq km per group with a density of 55 birds per sq. km. The maximum distance flown non-stop was about 180 m and prior to flying, they usually gain height by moving up a tree or tall shrub. Black Drongos are often seen foraging near these babblers. 
It builds its nest in a tree, concealed in dense masses of foliage. The normal clutch is two to four turquoise blue eggs, although up to five may be laid by birds in the hills of Sri Lanka. The eggs hatch after 18 to 21 days. The parent bird often stands on the rim of the nest rather than sit on the chicks. Brood parasitism by the Pied Cuckoo (Clamator jacobinus) is known. Chicks are fed mainly insects and the occasional lizard.In an exceptional case, Jungle Babblers have been seen seen feeding the chicks of the Yellow-billed Babbler. Like most other birds, the parents take care of nest sanitation, removing the fecal sacs of the young.
1. ^ BirdLife International (2004). Turdoides affinis. 2006 IUCN Red List of Threatened Species. IUCN 2006. Retrieved on 12 May 2006.
2. ^ Rasmussen, PC & JC Anderton (2005) Birds of South Asia: The Ripley Guide. Smithsonian Institution & Lynx Edicions. Vol 2. p. 447
3. ^ Davidar,ERC (1994) Exotic diet of Whiteheaded Babblers Turdoides affinis (Jerdon). J. Bombay Nat. Hist. Soc. 91(2):321
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5. ^ Johnsingh,AJT; Paramanandham,K; Murali,S (1982) Foraging behaviour and interactions of Whiteheaded Babbler Turdoides affinis with other species. J. Bombay Nat. Hist. Soc. 79(3):503-514.
6. ^ Johnsingh,AJT; Paramanandham,K (1982) Group care of White-headed Babblers Turdoides affinis for a Pied Crested Cuckoo Clamator jacobinus chick. Ibis 124(2):179-183.
7. ^ Raj,PJ Sanjeeva (1964) Communal breeding in the Whiteheaded Babbler [Turdoides affinis (Jerdon)] in Tambaram, Madras State. J. Bombay Nat. Hist. Soc. 61(1):181-183.
8. ^ Zacharias,VJ; Mathew,DN (1977) Malabar Jungle Babbler Turdoides striatus malabaricus (Jerdon) and Whiteheaded Babbler Turdoides affinis affinis (Jerdon) jointly caring for the chicks of the latter. J. Bombay Nat. Hist. Soc. 74(3):529-530.
9. ^ Jeyasingh,DEJ (1976) Faecal feeding in the Whiteheaded Babbler Turdoides affinis (Jerdon). J. Bombay Nat. Hist. Soc. 73(1):218-219.
10. ^ Khacher,Lavkumar (1978) Faecal feeding in the Whiteheaded Babbler, Turdoides affinis (Jerdon) – a rejoinder. J. Bombay Nat. Hist. Soc. 75(2):490-491