A martial eagle with a wingspan of nearly 2 meters targets a lion cub on the African savanna, undeterred by the risk of being detected and attacked by the lioness.
In December 2012, guides at the Maasai Mara National Reserve in Kenya witnessed a series of hunting incidents aimed at one of the top predators on the plains. An adult martial eagle followed a pride of lions for weeks, waiting for the right moment to swoop down and kill a total of three lion cubs. “The eagle is really targeting the lions,” commented R. Stratton Hatfield, a PhD researcher at Wageningen University in the Netherlands.
Martial eagle catching a 3-week-old lion cub in Mara North Reserve, Kenya. (Photo: Jes Lefcourt).
Although lions may dominate their surrounding territories, this incident and many similar cases indicate that African lions (Panthera leo) are not always at the top of the food chain. In fact, the martial eagle (Polemaetus bellicosus) is likely to prey on lion cubs whenever the opportunity arises, according to research by Hatfield and colleagues published in the journal Ecology and Evolution.
The martial eagle’s wingspan can exceed 1.8 meters. Female martial eagles weigh over 4.5 kg, while males typically weigh around 3.2 kg. Despite being similar in size and ecosystem to golden eagles, martial eagles often kill larger prey. They swoop down and drive their sharp talons into the spine behind the skull of their prey, sometimes taking down impala or young gazelles that are heavier than themselves.
Only recently, Hatfield’s team discovered that martial eagles also prey on other carnivores. The research team collected information on seven cases, including the 2012 incident, describing martial eagles hunting young lions, leading to the deaths of seven cubs and one near-fatality. Hatfield suspects that most cases involved large female eagles, although there were two cases involving immature eagles. The earliest case occurred in 2008 when a photographer captured an eagle feeding on a recently killed lion cub, while the most recent case took place in 2023, when a safari guide saw an immature eagle kill a lion cub so large it could not carry it away.
Despite their aerial hunting skills, martial eagles often face the risk of counterattacks. In one failed attempt, a martial eagle swooped down to catch a 6-week-old lion cub right next to its mother. The lioness detected the approaching danger and lunged to attack the eagle. The eagle dodged the attack and failed to catch the cub. Hatfield speculates that it did not see the lioness.
Amy Dikeman, a conservation biologist at the University of Oxford in the UK, is not surprised that eagles continuously target lion cubs if the tactic proves successful. Dikeman leads Lion Landscapes, a nonprofit organization focused on the harmonious coexistence of humans and wildlife in Kenya and Tanzania. She believes that Hatfield’s conclusions are quite reasonable. According to her, the eagle is just one of the threats that lions face, similar to hyenas or male lions from rival prides. Eagles are not a conservation threat to big cats. Martial eagles are not selective about their prey and some have even been known to attack the young of cheetahs and leopards. The risks often come from both sides; lions can also hunt adult eagles or young ones in their nests.
The martial eagle is classified as a vulnerable species by the International Union for Conservation of Nature. Like other large raptors in Africa, they face habitat loss, poaching, electrocution, and mistreatment.
