Jumbo threat to martial eagles
Martial eagles are apex predators, but there are 60% fewer of them now than 20 years ago, due largely to unlikely culprits: elephants.
Researchers who attached GPS trackers to eight martial eagles in the Kruger National Park said the birds’ preferred well-treed habitats were under threat.
“Tree cover [in Kruger] has undergone substantial change over the last half century, with some areas reducing in woody cover by up to 64%,” said Rowen van Eeden of the Percy FitzPatrick Institute of African Ornithology at UCT.
This was due to a combination of a rising elephant population and fires, but “tree fall rates in areas accessible to elephants may be up to six times higher”.
A previous study found that the decline of Kruger’s martial eagle population was highest in areas
with the big elephant populations.
Writing in the journal PLOSone, Van Eeden said his team had tracked two martial eagles that abandoned their territories, which may have been due to “shortages of prey, mate loss, low breeding success or limited appropriate breeding habitat”.
Three of the eight eagles tracked over three years died — two in hunters’ traps in Mozambique and one due to suspected electrocution in Swaziland.
Van Eeden said threats to the birds — the largest eagle species in Africa — included persecution, habitat transformation, electrocution and drowning in farm reservoirs.
There were an estimated 800 mature birds left in South Africa, Lesotho and Swaziland.