Although not the biggest eagle in Africa, the Crowned Eagle is considered the most powerful and ferocious eagle based on the size of its prey. Weighing in at 2.5 – 4.5 kg, it regularly kills prey heavier than itself. Forest mammals like Vervet monkeys and duiker (25kg) are never safe when this eagle is near. Africa’s biggest eagle is the Martial Eagle which can weigh over 6kg but prefers to prey on animals like Guineafowl and reptiles.
Also known as the Leopard of the Sky for its hunting abilities, the Crowned Eagle is well camouflaged with bars and blotches on the chest and a slate grey upper side. This colouring makes it disappear in a forest environment, especially because it tends to sit inside the tree canopy instead of on top like most other eagles.
To adapt to the forest environment, the Crowned Eagle has a long tail and broad, rounded wings. The combination of these two makes it extremely agile and fast which is one of the main reasons why it is the only eagle that preys on monkeys actively. Monkeys are very alert and quick, making them difficult to hunt, especially in a group. The male and female Crowned Eagle often hunt as a pair, while one eagle distracts the monkeys, the other makes the kill. With powerful feet and massive talons it can kill a monkey in one blow. This is essential because monkeys have strong hands and can easily damage an eye or a wing of the eagle.
During breeding time crowned eagles become much more visible and vocal as they make undulating areal displays at heights of up to 1km. They can be noisy during these times with a loud ‘kewee kewee kewee’ call from the male. This ritual is normally associated with breeding, but could also be an act of territorial domination.
The nest of a Crowned Eagle is a huge structure of sticks which is repaired and enlarged every breeding season, making the nests grow bigger and bigger. Some nests grow to be about 2.3 metres across making them the biggest nests of all the eagle species.
You have a chance of seeing this species in Kenya if you are touring Mt.Kenya Forest Reser, Nairobi National Park, Aberdare National Park, Kakamega tropical rain forest and Mau Forest.