Martial Eagles

The Martial Eagle population is declining rapidly throughout its range in Africa and is now classified as endangered.  The current nest on the 28,000Ha Selati Game Reserve, situated in the Limpopo Province of South Africa, offers an excellent opportunity to document and research the breeding biology of this, Africa’s largest eagle. We are requesting assistance to raise funds to live-stream an endangered Martial Eagle nest on the reserve. We require R50,000, which will be used to purchase a camera that will send real-time images to us of the nest, and fencing to protect the nest from predators.

“BirdLife South Africa welcomes the Selati Wilderness Foundation’s plans to install a live-streaming camera on a Martial Eagle nest on their reserve. This project will help create awareness for the conservation plight of one of Africa’s most iconic eagles. Given the recent up-listing of Martial Eagles to Endangered, there is an urgent need for well-informed and effective conservation action. The proposed camera can assist in this by providing the opportunity to gain new insights into the breeding biology and general ecology of this species.”
Christiaan Willem Brink
Raptor and Large Terrestrial Bird Project Manager: BirdLife South Africa

The Martial Eagle, Polemaetus bellicosus, is a large powerful eagle (78-83 cm) and weighing 3.3 to 4.7 kg (Taylor,2015). The females are considerably larger than the males. Martial Eagles can be identified by their dark backs, throat neck and head, contrasting with the white underbelly which is spotted. They are the largest eagle in Africa. They occur though out sub-Saharan Africa excluding the lowland forests of west Africa. Although they may be encountered anywhere in South Africa but more frequently in protected areas, especially the Transvaal Lowveld and the Kgalagadi Transfrontier Park (Barnes 2006c). They are however seldom seen in the mountains of Lesotho.  Outside protected areas their territory sizes vary between 300 and 1000 sq.km. (van Zyl, 1992). In Kenya, Brown et.al.  recorded territory sizes of 130km.sq. in 1982. Tarboton and Allan (1984) suggested 1000 mature individuals in the former Transvaal, with 137 pairs in the Kruger National Park, numbers are much less today. Murn et.al. (2012), estimated a breeding population of 110 mature individuals in the Kruger National Park based on their 2012 aerial survey of nests, a decrease of at least 50%. The Swaziland population has dropped from 40 mature pairs in 2011 (Parker, 2011) to 14 mature individuals in 2008 (Monadjem and Rasmussen, 2008). Due to habitat and land use change and persecution Martial Eagles have disappeared from much of their former range and are now categorized as “endangered” in southern Africa (Taylor et. al., 2015).

John Davies of EWT assisting with the nest research on Selati
Juvenile Martial Eagle

A Martial Eagle pair has successfully bred on Selati for a number of years. With the assistance from John Davies of the Endangered Wildlife Trust (EWT) Birds of Prey Programme we were able to ring and measure the fledglings in 2020.

In 2021/2 we aim to place a real-time camera at the nest to document the Martial Eagles breeding biology including, behaviour, incubation, chick development and fledging, prey selection, and post-fledging dependence on the nest.  Incidental nest observations have been recorded previously but thorough documentation of a breeding cycle from nest reconstruction to post-fledging has not been undertaken anywhere. A significant advantage of the technology to be used to collect images is that there will be no disturbance at the nest during the breeding/fledging period.  All images will be collected by a camera controlled by a Raspberry Pi computer programmed to send the images remotely by wifi.  The camera will be powered by a solar-charged battery which will not need to be visited for the duration of the breeding event. The nest is vulnerable to predation even though it is 24m up in a Knobthorn tree. It will be necessary to protect the solar panels, battery, and computer equipment from possible damage by inquisitive elephants, rhinoceros, buffalo, lions, and the chick from leopards. To prevent this, a perimeter electric fence is envisaged.

Tagging and measuring of a Juvenile Martial Eagle

The images collected we be analysed and interpreted by specialists.  In addition, the environmental students visiting the Eco-training centre on the Selati reserve will be able to study the images during their training. The results of the research will be made available through the Selati Wilderness Foundation NPC social media sites.