Martial Eagle

How The Peregrine Fund is helping

The Peregrine Fund has been working in Kenya for decades, striving to conserve the birds of prey found there and their habitats. Through environmental education efforts and emergency response training, we are working to put a stop to the common practice of poisoning carcasses to kill large predators, which also kills a host of wildlife including vultures, eagles, and other scavenging birds. These efforts will certainly benefit all raptors of the region, including the Martial Eagle. Additionally, our efforts in scientific research, habitat conservation, education, and community development help conserve birds of prey around the world. We also supply literature to researchers from our avian research library, which helps scientists around the world gather and share important information on raptor conservation.

Where it Lives

The Martial Eagle is found throughout much of sub-Saharan Africa. It can be found in over 40 countries in this region including Angola, Benin, Botswana, Burkina Faso, Ethiopia, Ghana, Kenya, Malawi, Mozambique, Namibia, Rwanda, Senegal, South Africa, Tanzania, Uganda and Zimbabwe. 

This majestic eagle normally inhabits open grasslands that are scattered with large trees. It can also be found in scrubby, more arid areas, as well as wooded savannas, or riparian forests. If you are ever in Martial Eagle habitat, spend some time scanning the tops of tall trees, where this eagle likes to perch. Another place to look for these birds is on top of power pylons! The construction of these structures has allowed this eagle to move into some areas devoid of trees. 

What it does

The Martial Eagle is a large bird of prey and it is also quite stunning. It soars through the skies on broad, dark wings. The adults' head, throat and upper breast are a dark, chocolate brown. This rich brown contrasts with the bird's underparts which are bright white and dotted with brown spots, looking almost as if someone took a paintbrush and splattered the bird's underparts with brown paint!  Adults have piercing, yellow eyes. While both adult male and female Martial Eagles have the same plumage patterns and coloration, the females of this species are noticeably larger than the males. This is called sexual dimorphism and is common in many raptors, but it is particularly pronounced in these eagles.

The Martial Eagle is a master soarer. It can spend a lot of time flying through the sky at great heights. 

Like many raptors, these eagles are top predators – they hunt other animals for food but no animals hunt them on a regular basis. For most top predators, their only threat is humans. Top predators, such as the Martial Eagle, play an important role in nature by helping to control populations of prey animals and maintain a balance in the ecosystems where they live.

Why it needs our help

Throughout much of this beautiful eagle's range,  it is facing multiple and serious threats. Perhaps one of the biggest threats it faces is habitat loss. Many of the large trees they use for nesting are being cut and their habitat is being converted to agricultural fields. Even where habitat remains, these beautiful eagles are also being poisoned! Ranchers will often lace a dead cow, sheep or other bait with highly toxic poisons in an attempt to kill jackals, lions, hyenas and other predators that they fear might prey on their livestock. Because these eagles scavenge on carcasses, many of them die after ingesting these poisons, which are also responsible for the deaths of many other animals including vultures and storks. If this weren't bad enough, scientists have documented that some of these eagles end up accidentally drowning in farm reservoirs, too. Many farmers shoot these eagles because they fear the eagles will kill their livestock. Other threats include electrocution on power poles and collisions with power lines.

Sadly, all of these threats put the Martial Eagle's population at great risk. In fact, it is now classified as Endangered by BirdLife International. 

What it eats

As you can probably imagine, a large eagle like the Martial Eagle is fully equipped to hunt a wide variety of prey. It uses its strong feet and sharp talons to catch medium-sized mammals, birds, and reptiles. Some animals on the Martial Eagle's menu include guineafowl, francolins, bustard, flamingo, hornbills, ostrich chicks, monitor lizards, monkeys, mongoose, dikdiks, hares, hyraxes, and steenboks. It has also been known to feed on other raptors, and some large ones to boot. It has preyed on Spotted Eagle-owls and White-headed Vultures.  Some researchers have also documented it occasionally feeding on livestock, mostly lambs, piglets, and kids. It is unclear how much livestock these eagles kill each year, especially since they are known to scavenge, and, in many instances, are likely taking advantage of finding dead farm animals, rather than killing them outright.  

This powerful hunter employs a diverse array of hunting tactics to catch its prey. One of the most-used techniques is to hunt by soaring. When it spots an animal moving below it hovers overhead and strikes at its prey after a deep stoop (dive). 

Nests, Eggs, and Young

Large eagles tend to build large nests and the Martial Eagle is no exception. Their nest can measure between 1·2–1·5 meters across, and 60 cm deep! They build their nest with large sticks and they often line it with green leaves. Nests are built in the fork of a large tree. In areas with little or no trees, they can nest on cliff ledges, or, in some areas, on power poles and pylons. These eagles are quite territorial and some pairs have maintained the same territory for a number of years.

When it is time to breed, the female and the male will engage in simple courtship displays - such as circling together in the sky or vocalizing to each other from a perch. The female usually lays only one egg, though researchers have found that she will sometimes lay up to two eggs, though only one nestling survives.

After the female lays the egg, it must be incubated for around 50 days. While the female does the majority of the incubating, the male does assist from time to time, allowing the female to move about, stretch, and feed. After the nestling hatches, it is covered in fluffy down feathers. Its upperparts will be covered in dark gray down and its underparts will be white. As it grows, it will require a lot of care from its parents. The male will do most of the hunting during the first seven weeks of the nestling's life, leaving the female with the responsibility to feed and protect her young.

After nearly two months, the female will begin to venture further from the nest and begin to hunt to provide food for her nestling as well. Over the next few months, the eaglet will develop quickly and after about 100 days, it will be ready to fledge, or fly for the first time. Even after it is flying, it will still rely on its parents to teach it how to hunt and to avoid danger. It will remain in its parents territory for 8 to 12 months before heading out on its own. 

Martial Eagle and the World Center for Birds of Prey

The World Center for Birds of Prey is a great place to begin learning about eagles. Though we don't have any Martial Eagles as part of our Avian Ambassador crew, we do have a live Harpy Eagle at the center. You can meet Grayson, a male Harpy Eagle, in his specially-designed chamber. We also have a live Bald Eagle and a young Ornate Hawk-Eagle on site, as well as a pair of Bateleur Eagles, which overlap in range with the Martial Eagle. We have a mounted eagle on display, real eagle feathers you can touch, and more.

References:

BirdLife International. 2020. Polemaetus bellicosus. The IUCN Red List of Threatened Species 2020: e.T22696116A172287822. https://dx.doi.org/10.2305/IUCN.UK.2020 3.RLTS.T22696116A172287822.en. Downloaded on 05 August 2021

Global Raptor Information Network. 2021. Species account: Martial Eagle Polemaetus bellicosus. Downloaded from http://www.globalraptors.org on 5 Aug. 2021

Kemp, A. C., P. F. D. Boesman, and J. S. Marks (2020). Martial Eagle (Polemaetus bellicosus), version 1.0. In Birds of the World (J. del Hoyo, A. Elliott, J. Sargatal, D. A. Christie, and E. de Juana, Editors). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.mareag1.01

Naude, V.N., Smyth, L.K., Weideman, E.A., Krochuk, B.A. and Amar, A., 2019. Using web-sourced photography to explore the diet of a declining African raptor, the Martial Eagle (Polemaetus bellicosus). The Condor: Ornithological Applications, 121(1), p.duy015.