the fitzpatrick report

to predict where Martial are likely to nest on pylons, and has used it to estimate how many pairs of eagles nest on pylons. So far 92 Martial territories have been found through aerial surveys, and the models predict a further 50 eagle territor­ ies along non-surveyed lines. The 140 or so Martial Eagle nests on the South African transmission network is clearly of national importance for this declining species. Birders can help by reporting Martial Eagle sightings and nest locations, particu- larly those on power pylons, to martial [email protected]. In the we have colour-ringed 18 Martial Eagles and are especially keen to obtain sightings or photographs of these . Please include the date and location with all sightings submitted.

For more information, contact The Director, Percy FitzPatrick Institute of African Ornithology, University of Cape Town, FORCES Rondebosch, South 7701. marshalling E-mail [email protected], marietjie froneman tel. +27 (0)21 650 3291 or he FitzPatrick Report in the July/ equally suitable for the species. This sug- the size of the Kruger National Park. They visit www.fitzpatrick.uct.ac.za August 2013 issue of African Birdlife gests that the total Martial Eagle popu- spend as much as 60 per cent of their time highlighted the apparent plight of lation in Kruger is smaller than that of beyond boundaries, travers- below Most adult Martial Eagles hold MartialT Eagles. The comparison of SABAP1 (approximately 1 600) and ing much of the lowveld and adjacent discrete territories whereas juveniles tend to roam widely. and 2 data showed declines in reporting (approximately 2 000). . Thus even parks as large as chris van rooyen rates of up to 60 per cent of the species However, not all adults remain on their Kruger are too small to adequately protect across . Particularly alarm- territories year round. One female left her such a wide-ranging species. By identify- ing was the fact that these declines have territory, travelling back and forth between ing and mitigating the main sources of adults Juveniles occurred even in the country’s largest pro- Kruger and Mozambique for 272 days, and mortality we hope to successfully conserve tected areas, including the Kruger National covered more than 2 200 kilometres before the species. Park, long considered a stronghold for she was eventually killed in rural Mozam- Compounding the problems of dispersal the species. As a result, Rowen van Eeden bique. Evidently, during these travels, the beyond the park boundaries, breeding suc- started a PhD study to understand the eagles are exposed to a greater risk of cess also appears to have been surprisingly drivers of the declines of these impressive human-induced mortality, with surround- low during the 2013 and 2014 seasons, av- birds in Kruger. ing lands acting as a ‘sink’ for the Kruger eraging just 0.24 chicks fledged per pair per By GPS tracking Martial Eagles, Rowen population. To date, deaths of tagged year, only half the expected 0.5 (a fledgling has begun to unravel the mystery of how Martial Eagles have also resulted from every second year) reported elsewhere in the eagles use their . Over 70 000 electrocutions and conflict during territo- Africa for this species. The possible reasons GPS locations have been recorded to date rial disputes with conspecifics. for this low productivity will be investig­ and are being used to understand the Young eagles are probably most at risk of ated in 2015. eagles’ habitat requirements. The territory dying as they are thought to travel widely In another research project, Masters stu-­ size of adults averages 110 square kilo- before claiming a breeding territory. The dent Jessie Berndt has explored the impor- metres, which is similar to that of a pride GPS tracking has shown that after fledg- tance of Martial Eagles nesting on Eskom’s of lions (100 to 250 square kilometres) ing, juvenile Martial Eagles remain on the power transmission pylons. This is particu- and greater than that of leopards (15 to parental territory for up to nine months larly important in the largely treeless , 40 square kilometres). Based on these before they disperse over large distances. where natural nesting sites are scarce. crude figures, Kruger could potentially The three juveniles tracked thus far each In collaboration with supervisors Andrew hold at most 175 breeding pairs of eagles, ranged over an area averaging 35 000 Jenkins, Res Altwegg and Arjun Amar, Jessie assuming all habitat within the park was square kilometres, more than 1.5 times has developed a habitat-association model

18 african birdlife march/april 2015 The FitzPatrick Report 19