The Philippine eagle is an endangered species of eagle native to forests in the Philippines. It is considered the largest of the extant eagles in the world in terms of length and wing surface. The eagle has a dark face and a creamy-brown nape and crown. Its nape is adorned with long, brown feathers that form a shaggy, manelike crest. The back of the Philippine eagle is dark brown, while the underside and underwings are white. The heavy legs are yellow, with large, powerful, dark claws, and the prominent, large, high-arched, deep beak is a bluish-gray. The eagle's eyes are blue-gray. Juveniles are similar to adults except their upperpart feathers have pale fringes.
Philippine eagles are found in the Philippines and occur on four major islands: eastern Luzon, Samar, Leyte, and Mindanao. They inhabit moist and montane forests, particularly in steep and rugged areas.
Philippine eagles are generally solitary and spend time singly on in breeding pairs. They are active during the day and at night they rest. Philippine eagles primarily use two hunting techniques. One is still-hunting, in which they watch for prey activity while sitting almost motionlessly on a branch near the canopy. The other is perch-hunting, which entails periodically gliding from one perch to another. While perch-hunting, they often work their way gradually down from the canopy on down the branches, and if not successful in finding prey in their initial foray, they fly or circle back up to the top of the trees to work them again. Eagle pairs sometimes hunt troops of monkeys cooperatively, with one bird perching nearby to distract the primates, allowing the other to swoop in from behind, hopefully unnoticed, for the kill. Philippine eagles communicate vocally and the most frequently heard noises include loud, high-pitched whistles ending with inflections in pitch. When begging for food, juveniles are known to produce a series of high-pitched calls.
Philippine eagles are carnivores. Their diet includes monkeys, birds, flying foxes, giant cloud-rats, Asian palm civets, flying squirrels, tree squirrels, fruit bats, reptiles (large snakes and lizards) and even other birds of prey. They will also feed on flying lemurs in some locations and have been reported to capture even young pigs and small dogs.
Philippine eagles are monogamous and once paired, a couple remains together for the rest of their lives. If one dies, the remaining eagle often searches for a new mate to replace the one lost. During the breeding season that takes play in July, Philippine eagles perform courtship displays. The beginning of courtship is signaled by nest-building, and the eagle remaining near its nest. Aerial displays include paired soaring over nesting territory, the male chasing the female in a diagonal dive, and mutual talon presentation, where the male presents his talons to the female's back and she flips over in midair to present her own talons. The willingness of an eagle to breed is displayed by the eagle bringing nesting materials to the bird's nest. The nest is usually built on a tall tree with an open crown; it is lined with green leaves and can be around 1.5 m (4.9 ft) across. The female typically lays one egg, although occasionally two have been reported. The egg is incubated for 58 to 68 days (typically 62 days) by both parents, but the female does the majority of incubating during the day and all of it at night. Both parents help feed the newly hatched eaglet. The chick fledges after 4 or 5 months and both parents take care of it for a total of 20 months. Females usually become reproductively mature at five years of age and males at seven.
Philippine eagles are threatened primarily by deforestation through logging and expanding agriculture. Old-growth forest is being lost at a high rate, and most of the forest in the lowlands is owned by logging companies. Mining, pollution, exposure to pesticides that affect breeding, and poaching are also major threats. Additionally, Philippine eagles are occasionally caught in traps laid by local people for deer.
According to the IUCN Red List, the total Philippine eagle population size is around 180-500 mature individuals, which is around 250-750 individuals in total. According to Wikipedia resource in 2015, about 600 Philippine eagles were estimated to be left in the wild. Currently, this species is classified as Critically Endangered (CR) on the IUCN Red List and its numbers today are decreasing.