The Martial Eagle population is declining rapidly throughout its range in Africa and is now classified as endangered. There is a Martial Eagle nest at Selati Game Reserve that has given us an excellent opportunity to document and research the breeding biology of Africa’s largest eagle. During 2021 we installed a live stream camera system at the nest on the reserve and we teamed up with BirdLife SA to make the information gathered from this system available to enthusiasts and interested parties across the globe. Below you will find further information about our progress with this ongoing project.
The Martial Eagle, Polemaetus bellicosus, is a large powerful eagle (78-83 cm) and weighs 3.3 to 4.7 kg. 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, they occur more frequently in protected areas, especially in the Mpumalanga and Limpopo Lowveld and the Kgalagadi Transfrontier Park. The decline in the Martial Eagle population in South Africa has been the subject of numerous scientific studies. In 2017, the Cambridge University Press published Quantifying the decline of the Martial Eagle Polemaetus bellicosus in South Africa by Amar and Cloete. This study was based on data from the The Southern African Bird Atlas Project (SABAP) 1 and 2 and showed overall declines in reporting rates (population) of 60% over a 20-year period.
Martial Eagles have disappeared from much of their former range and are now categorized as “endangered” in South Africa.
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 fledgling in September 2020. We took the opportunity of this disturbance to place a camera trap at the nest. The images from the camera allowed us to document nest activity and prey species up until the fledgling left the nest.
The success of the camera trap exercise lead to decision to upgrade the system to a solar powered, real time imaging system capable of capturing motion activated still images and capable of streaming continuous live video footage of nest activity via a radio and Wi-Fi link. The system hardware was installed in August 2021 in anticipation of the eagle pair returning to start the biennial breeding cycle around April 2022.
This camera system at the nest will allow us 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 this technology is that there will be no disturbance at the nest during the breeding/fledging period.
The partnership with BirdLife South Africa will allow us to bring this unique wild life saga into the lives of many birding enthusiasts and will afford the opportunity to raise funds for conservation via a subscription-based membership. A panel of experts has been assembled to provide ongoing commentary and insights on what is unfolding on the nest. In addition to 24/7 access to live video footage from the nest, members will have access to ongoing commentary from the panel as well as curated highlights packages.
With the system in place, we were all set to go for the anticipated 2022 breeding cycle. Early signs were encouraging. Our first sighting of a Martial Eagle visiting the nest was on 3 February 2022. However, this was not to be. The 2020 pair did not return as anticipated. Instead, we had a showing of a pair much later between 16 June and 2 July 2022. And, despite signs of intent (some nest preparation) it transpired that the male was a juvenile, not the 2020 male, and was too young to mate. We suspect that the 2020 male died and the female paired up with the new young male. We anticipate that this pair will return to breed next year and we can’t wait to capture the action and tell the story.
Bone fide researchers will be afforded free access to the information generated by this initiative.