White-bellied woodpecker

The white-bellied woodpecker, scientifically known as Dryocopus javensis and sometimes referred to as the great black woodpecker, is a substantial avian species inhabiting the evergreen forests of the tropical Indian subcontinent and Southeast Asia. It ranks among the largest woodpeckers found in Asia, surpassed only by a few other species in size. The species is known for its distinct drumming patterns and loud vocalizations, which are more pronounced than those of smaller woodpeckers.

Physical Characteristics and Size

Adults of this species are impressive in stature, typically measuring between 40 to 48 cm (16 to 19 inches) in length, placing them among the largest living woodpecker species. Their weight can range from 197 to 350 grams. Standard measurements for the wing chord fall between 20.5 to 25.2 cm, with the tail measuring 14.3 to 18.9 cm. The bill is substantial, ranging from 4.6 to 6 cm in length, and the tarsus measures 3.2 to 4.3 cm.

Subspecies and Distribution

Fourteen subspecies of the white-bellied woodpecker have been described, reflecting its wide geographic distribution. Notable subspecies include D. j. hodgsonii, found primarily in the Western Ghats of India, and various island forms across Southeast Asia. Unfortunately, many of the island subspecies are facing significant threats, with several populations being endangered or even extinct. The distribution and extent of white plumage can vary considerably among these subspecies.

Behavior and Ecology

The white-bellied woodpecker is typically observed alone or in pairs, though sometimes a third bird may join them. They are known to spend considerable time, sometimes up to an hour, foraging at a single productive tree. Their diet primarily consists of insects, such as ants and grubs, which they extract from beneath tree bark. They also supplement their diet with fruit. Despite their generally shy nature, they have been observed nesting in areas close to human activity and frequently used trails. Breeding usually occurs from January to May, with nests constructed in large, dead trees, often in open forest settings. The typical clutch size is two white eggs. The species roosts within tree cavities.

Vocalizations and Drumming

This large woodpecker produces a range of sounds, including loud drumming, particularly noticeable during the breeding season. Their calls vary from a short, sharp 'kuk' to more melodic and resonant sounds like 'kyuk', 'keu', and 'kee-yow'. Longer calls are often emitted just before the bird takes flight, serving possibly as communication or territorial signals.