The crested serpent eagle (Spilornis cheela) is a medium-sized bird of prey found across tropical Asia. Recognized for its distinctive crested head and striking appearance, it is a master hunter of snakes and other reptiles.

With a wide range spanning the Indian Subcontinent, Southeast Asia, and East Asia, this eagle plays a crucial role in controlling reptile populations within its habitats. Let's explore its unique characteristics, behavior, and ecological importance.

Appearance and Characteristics

This dark brown eagle has a stocky body, with rounded wings and a short tail. The most notable feature is its black-and-white fan-shaped crest, which gives it a thick-necked look. The bird's facial skin and feet are yellow, while its underside is marked with white and yellowish-brown spots. When perched, the eagle's wings do not reach the tail tip, but in flight, its broad wings are held in a shallow "V" shape. The tail and flight feathers have broad white stripes, enhancing its distinctive look.

Young crested serpent eagles show more white on their heads, and as they mature, their crests become more prominent. The unfeathered legs are covered with hexagonal scales, a characteristic feature of the species.

Distribution and Subspecies

The crested serpent eagle has a wide distribution across tropical Asia, with 21 named subspecies. The nominate subspecies is found along the sub-Himalayan range, while others inhabit regions like Peninsular India, Indochina, the Malay Peninsula, Sumatra, and various small islands. Some subspecies, such as the Bawean serpent eagle, are critically endangered, with only a few pairs remaining. The eagle's widespread range is complemented by its adaptability, though populations on smaller islands are often smaller due to insular dwarfism.

The Crested Serpent Eagle (Spilornis cheela)

Video by WildFilmsIndia

Feeding and Hunting Behavior

True to its name, the crested serpent eagle specializes in hunting reptiles, particularly snakes and lizards. It hunts over forested areas, often near wetlands, where it searches for its prey. The eagle employs a sit-and-wait strategy, perched on trees or soaring in search of prey. When alarmed, it can raise its crest, making its head appear larger and more intimidating. Its distinctive call, often described as a "Kluee-wip-wip", is heard frequently, especially in the mornings.

Breeding and Nesting

Breeding begins in late winter, with pairs establishing territories. Nests are typically built in riverine trees or other high spots. Both male and female work together to build the nest, but it is the female who incubates the eggs. The nest is often refurbished each year, though some birds, especially in places like Penang, may build fresh nests annually. One egg is the usual clutch, but occasionally two are laid, with only one chick surviving to fledge after about two months.

Conservation and Ecological Importance

While the crested serpent eagle remains relatively common overall, certain island populations are facing declining numbers, especially the Bawean serpent eagle. Habitat loss, alongside the small populations of island subspecies, has contributed to these declines. Conservation efforts are essential to ensure the survival of the more isolated populations.

The eagle plays a significant ecological role by helping control reptile populations. It often shares its nesting sites with other species, such as the cinereous chickadee, which nests close to the eagle's perch to benefit from protection against predators.

The crested serpent eagle is a remarkable bird, well adapted to life in the dense forests of tropical Asia. Its striking appearance, specialized diet, and fascinating behavior make it a valuable part of its ecosystem. However, with some subspecies at risk, continued conservation efforts are needed to protect this majestic raptor.