comparison, the temperate-zone-dwelling golden eagle is a frequent predator of other birds of prey. This may be due to more scarce prey resources in colder regions forcing eagles to pursue difficult prey such as this more frequently, whereas booted eagles in rich Africa biospheres may not need to do so as much. Nonetheless, a somewhat diverse range of raptorial birds have been identified as prey for martial eagles: the lanner falcon (Falco biarmicus), the peregrine falcon (Falco peregrinus), the spotted eagle owl (Bubo africanus) (with a surprisingly large number of 6 found at one nest in Tsavo East), the pale chanting goshawk (Melierax canorus), the hooded vulture (Necrosyrtes monachus) (in one case after a protracted aerial battle), the white-headed vulture (Trigonoceps occipitalis) and even Africa's largest bird of prey, the Cape vulture (Gyps coprotheres). As apex predators, martial eagles are themselves largely invulnerable to predation. A video exists that purportedly depicts a leopard killing a martial eagle but this eagle was misidentified as it actually features a leopard preying on an immature African fish eagle (Haliaeetus vociferus) (and, at that, one that was possibly grounded for unknown reasons). There are, however, verified (if rare) cases of caracals preying on sleeping martial eagles at night, by climbing trees and pouncing in an ambush. Additionally a case was reported where a honey badger killed an incubating adult martial eagle. It is possible that leopards may too ambush sleeping eagles, but post-fledgling martial eagles are known to be highly wary, and healthy individuals a great majority of the time will successfully evade potential dangers by day. Predation on nests of martial eagles, beyond those by humans, are little known, with no verified depredations known in the literature, but are likely to occur. Territoriality Despite their rather aerial existence, the territorial display of adult martial eagles is considered relatively unspectacular. Their display often consists of nothing more than the adult male or both members of a pair circling and calling over their home range area or perching and calling near nestlings. Compared to other large African booted eagles, this species infrequently “sky-dances” (i.e. undulation and dramatic movements high in the sky), but some are known with presumably the male martial eagle only engaging in shallow undulations. During mutual circling, the adult female may turn and present talons. Martial eagles are not known to “cartwheel” which is when two eagles lock feet and circle down,