Eagle Facts

  • The Harpy Eagle of central and southern America is the heaviest and most powerful eagle. They catch prey up to the size of monkey and sloth.
  • The White-tailed Sea Eagle is the largest bird of prey in the UK- it is slightly larger than the Golden Eagle. Only these two species are native to the UK.
  • The Golden Eagle is the most widespread eagle species coming from North America, Europe, Asia and parts of Africa.
  • Eagles are regarded as the King of Birds and in many cultures the eagle is regarded as a symbol of strength and power. The Bald Eagle is the US national bird.
  • The term eagle refers to the larger birds of prey. There are 68 recognised species of Eagle but are split into 4 groups.

Booted Eagles

This group known as booted eagles are so called as they all have feathers covering all the legs to the top of their feet (most raptors have bare legs or tarsi). Included in this group is the Golden Eagle, Steppe Eagle, Tawny Eagle, Verraux (Black) Eagle and Wedge-tailed Eagle. Some of this group is known as the hawk-eagles such as Ornate Hawk-Eagle and African Hawk-Eagle. These are much smaller than other eagles and generally they live in forests and therefore have short wings and long tails (see Hawks).

As this group has the highest number of species they are the most widespread and live in many different regions; they also have the most varied diet of any eagle group. Some like the Golden Eagle mostly hunts medium-sized mammals but will take birds, reptiles and up to young deer. The Tawny Eagle and Steppe Eagle will both congregate around termite nests and catch the emerging insects which are usually triggered by the rains.

Golden Eagle (aquila chrysaetos)
African Fish Eagle (Haliaeetus vocifer)

Sea/Fish Eagles

This group has some of the largest species of eagle. The largest of this group of eagles is the Steller’s Sea Eagle. There are 10 species of Sea or Fish-Eagle and the group also contains the White-tailed Sea Eagle, African Fish EagleBald Eagle and Steller’s Sea Eagle. The rarest species of this group is the Madagascan Fishing-Eagle.

The undersides of the eagle’s feet are very rough which enables them to grip a slippery fish more easily. Fish eagles do not exclusively eat fish some will catch birds, mammals and feed on carrion. Some pairs of our native White-tailed Sea Eagle specialise in catching different prey.

Forest Eagles

This small group of 4 species contains the most powerful eagle, the Harpy Eagle. It originates from the rainforests of Central and South America. The eagles in this group tend to hunt animals that live in the trees, such as monkeys and sloths. As their prey can grip very tightly to a tree these eagles have extremely powerful feet and their weight helps them to dislodge prey.

Another forest eagle is the Philippine Eagle, or Philippine Monkey-eating eagle. They will sometimes hunt by gliding over the treetops looking for monkeys and large birds such as hornbills. This eagle is classified as endangered and much work is being done to ensure their survival. Birds are captive bred and then released into the wild. As these eagle species all live in rainforest they are in danger of extinction as the forests are destroyed.

Serpent Eagles

These eagles specialise in catching snakes, hence the name, but also lizards, frogs and birds. There are 22 species. Most of these species have extra-thick feathers and layered scales on the legs to try and prevent snake biting the skin. They also generally have large heads with long feathers that fan out. Their toes are short and stubby which help them catch and hold on to wriggling snakes. The eagle kills the snake by crushing the head with its talons or beak, most smaller snakes are swallowed whole. The venom does not harm the eagle.

Bateleur (terathopius ecaudatus)

General Eagle Information

Eagles are generally old enough to breed at around four or five years old- their plumage usually gradually changes up until that time. It has long been believed that eagles pair for life. No studies have demonstrated this conclusively but it is believed to be true. However if one of pair dies the eagle will readily find another mate.

The exact lifespan of eagles are unknown in the wild but it is believed that if they survive to maturity they will live around 20-30 years. It is only recently that large number of some eagle species that are under study are individually marked and therefore more accurate information will become available.

Some species of eagle (mainly fish eagles) will perform spectacular courtship displays where the male and female will interlock feet while up high and plummet towards the earth or water, only releasing and the last possible moment.

Most eagle species will build nests either in a tree or cliff face. Occasionally some eagles will nest on the ground if no tree or cliff is available. Fish eagles tend to build the largest nest and will generally reuse the same nest each year and keep adding to it. One Bald Eagle nest in Florida was recorded at being over 20 feet high.

Most eagles lay 2 eggs but sometimes 3 or 4. The Harpy Eagle will only lay 1 egg every 2 years as the young can stay with parents for up to 18 months. Most eaglets leave the nest around 3 to 4 months old. They usually stays with parents for another 2 to 3 months learning how to hunt and then they are chased from the parents territory.

The Future of Eagles

You may think an eagle has no enemies. Sadly it does – and its greatest enemy is human beings. Throughout the world we have destroyed many of the eagles’ homes. We have cut down trees where they used to nest and we have built many roads, cities and resorts where they used to hunt. We have also polluted rivers and lakes with chemicals that kill the fish.

In many parts of the world farmers and fishermen shoot or poison eagles because they believe that the catch harm their livelihoods, but this has been shown many times to be untrue. It is against the law, in many countries, to harm an eagle but people continue to persecute them.

Fortunately there is still hope for eagles because many people care about them and are committed to their survival. Conservation groups (see Worldwide Raptor Conservation) around the world are fighting to protect the areas where eagles live, and to pass laws that will control pollution and stop the shooting and trapping of these magnificent birds.