About Hypothymis azurea (Boddaert, 1783)
This species is the black-naped monarch, with the scientific name Hypothymis azurea (Boddaert, 1783). Adult males measure approximately 16 cm in length. Their plumage is mostly pale azure blue, with the exception of a whitish lower belly. Males have a black nape and a narrow black gorget. Females have duller coloration, lack all black markings, and have grey-brown wings and back. Several geographically separated breeding populations show differences in the extent and shade of their markings. The subspecies found on the Indian peninsula is H. a. styani, which subsumes H. a. sykesi described by Stuart Baker; males of this subspecies have very distinct black markings and a whitish abdomen. Males of the Sri Lankan subspecies H. a. ceylonensis lack the black nape and gorget, and their blue plumage has a more purplish shade. H. a. tytleri, the subspecies from the Andaman Islands, has blue-grey underparts. The form from Car Nicobar Island, H. a. idiochroa, has a greyish white belly, while H. a. nicobarica from the southern Nicobars has a smaller and finer bill. The gape color ranges from yellowish to greenish. The call of the black-naped monarch is a sharp, abrupt skrip. The black-naped monarch breeds across tropical southern Asia, ranging from Iran and Sri Lanka eastward to Indonesia and the Philippines. This species typically occurs in thick forests and other well-wooded habitats. For the Indian population, main breeding season is reported as summer from May to July, and also more broadly as March to August. Two to three eggs are laid in a cup nest built in the fork of a tree. The nest is decorated with spider-egg cases. It is a neat cup lined with filaments of webbing and fungi, including species from the genus Marasmius. These fungi are known to produce antibiotics, which may protect the birds' young from infection. The female builds the nest, while the male guards the nesting site. The typical clutch size is three eggs. Both parents incubate the eggs and feed the hatchlings, which emerge after approximately 12 days of incubation. Black-naped monarchs have short legs, and sit very upright when perched prominently, in a posture similar to shrikes. They are insectivorous, and often hunt by flycatching. When alarmed or alert, they raise their nape feathers into a pointed crest. They join mixed-species foraging flocks, and are among the most significant members of such flocks in the Western Ghats. They are active in the understory of forest canopies. A study conducted in Sri Lanka found that the species is affected by human disturbance, with individuals receding from disturbed edges by about 75 meters. Although the species is largely resident, local seasonal movements have been recorded. Large spider webs, such as those of Nephila maculata, are known to trap black-naped monarchs. An astrovirus, a virus not previously recorded in passerines, has been detected in a black-naped monarch in Cambodia. The feather mite Proterothrix hypothymis (Pterodectinae: Protophyllodidae) has been described from black-naped monarchs in Vietnam.
