A Fierce and Deadly hunter… The Bonelli’s Eagle Hieraaetus fasciatus
If you were to search for an emblematic species which would define the importance of the Serranía de Ronda for wildlife, then the Bonelli’s Eagle Hieraaetus fasciatus would be the definitive and unequivocal choice. Among the rarest species of raptor in Europe, the Bonelli’s Eagle has perhaps, for the moment, its highest breeding density in the world right here in the Serranía!
With a wingspan of up to 1.8 meters the Bonelli is a medium sized eagle and although it is known to sometimes nest in trees in the Serranía its preference is for rocky crags and faces. The pairs form lifelong and all year round partnerships staying in or close to their breeding territories throughout the year. Usually nests are re-furbished during late December and early January. During this period pairs can be witnessed indulging in flight-play with one, normally the male, dropping a stick and the other retrieving it before it reaches the ground! The first egg is laid during February and although a clutch of 3 is possible the most usual is for 1 to 2 eggs. Incubation normally takes around 40 days and usually a single young is fledged after a further 60/65 days.
These eagles are extremely agile flyers and one of the most aggressive. Protection of the nest site during the breeding season is a spectacle that can provide the fortunate observer with a life time experience. The male will often pursue and sometimes inflict fatal injuries on much larger birds such as Griffon Vultures who venture too close to the nest. I have often seen unfortunate Griffons retreat from areas minus a few feathers! Unlike many other eagle species, the Bonelli’s are capable of flying-down their prey and over long distances. Most large raptors avoid long distance pursuit in order to save energy, but these eagles, once giving chase, will continue to fly-down prey over considerable distances. Hare, Rabbit, Partridge and other large birds form the largest part of their diet, although some reptiles are also taken.