crow-billed drongo Dicrurus annectens

Large dark drongo of open forested environments. Glossy black with a characteristically forked tail. Immature speckled with grayish-white on lower breast and belly. Thick dark bill gives a generally heavier-headed appearance than other similar dark drongos such as Black Drongo, with which it shares parts of its range; also prefers more forested environments than the latter. Aggressive and territorial, particularly during the breeding season, frequently mobbing raptors and corvids with great vigor. Like other drongos, boasts a varied repertoire; songs include a ringing “tsee-goo-gohgee!” Calls include bell-like gurgling notes, harsh chattering, and piercing whistles.