The crested serpent eagle, Spilornis cheela, is a medium-sized raptor with a robust build, characterized by its dark brown plumage, rounded wings, and short tail. Its most distinctive feature is the short black and white fan-shaped nuchal crest, which imparts a thick-necked appearance. The face is bare, with striking yellow skin that extends to the ceres, and the powerful feet are unfeathered, displaying heavy scaling. The underside is adorned with white and yellowish-brown spots, and when perched, the wingtips fall short of the tail tip. In flight, the broad wings form a shallow 'V', and the tail and underside of the flight feathers exhibit bold black and white bars.
The crested serpent eagle is a reptile specialist, hunting snakes and lizards over forested habitats and wet grasslands. It also preys on various other animals, including birds and mammals. This species is mostly sedentary, with some populations being migratory. They spend much of their time perched, calling frequently with a loud, piercing three or two-note call. Males in Taiwan have been observed to have larger home ranges than females. The species uses a sit-and-wait hunting strategy and is known to roost in densely foliaged trees.
The call of the crested serpent eagle is a distinctive and rising "Kluee-wip-wip," often heard in the late mornings.
