The Philippine eagle (Pithecophaga jefferyi), also known as the monkey-eating eagle or great Philippine eagle endemic to forests in the Philippines.
It is considered the largest of the extant eagles in the world in terms of length and wing surface, with Steller's sea eagle and the harpy eagle being larger in terms of weight and bulk.
The Philippine eagle has a wingspan of 184 to 220 cm (6 ft 0 in to 7 ft 3 in) and a wing chord length of 57.4–61.4 cm (22.6–24.2 in).
It has brown and white-colored plumage, and a shaggy crest, and generally measures 86 to 102 cm (2.82 to 3.35 ft) in length and weighs 4.7 to 8.0 kg (10.4 to 17.6 lb).
The Philippine eagle can be found on four major islands: eastern Luzon, Samar, Leyte, and Mindanao.
Among the rarest and most powerful birds in the world, it has been declared the Philippine national bird on 4 July 1995.
The level of sexual dimorphism in size is not certain, but the male is believed to be typically about 10% smaller than the female.
Evolution in the Philippine islands, without other predators, made the eagles the dominant hunter in the Philippine forests.
It is critically endangered, mainly due to massive loss of habitat resulting from deforestation in most of its range.
Killing a Philippine eagle is punishable under Philippine law up to 12 years in prison and heavy fines.
The first European to study the species was the English explorer and naturalist John Whitehead in 1896, who observed the bird and whose servant, Juan, collected the first specimen a few weeks later.
Upon its scientific discovery, the Philippine eagle was first called the monkey-eating eagle because in Samar, where the species was first discovered, that it preyed exclusively on monkeys.
Later studies revealed, however, that the alleged monkey-eating eagle also ate other animals, such as colugos, civets, large snakes, monitor lizards, and even large birds, such as hornbills.
This species has no recognized subspecies. Its nearest relatives are snake eagles (Circaetinae), such as the bateleur.
The Philippine eagle's nape is adorned with long, brown feathers that form a shaggy, manelike crest..
The largest numbers of eagles reside on Mindanao, with between 82 and 233 breeding pairs.
Each breeding pair requires a large home range (around 133 km2) to successfully raise a chick, thus the species is extremely vulnerable to deforestation.
The species' flight is fast and agile, resembling the smaller hawks more than similar large birds of prey. Life expectancy for a wild eagle is estimated to be from 30 to 60 years.
The complete breeding cycle of the Philippine eagle lasts two years. Like most eagles, the Philippine eagle is monogamous. Once paired, a couple remains together for the rest of their lives.
The female typically lays one egg. If an egg fails to hatch or the chick dies early, the parents likely lay another egg the following year.
The egg is incubated for 58 to 68 days. Both sexes participate in the incubation and both sexes help feed the newly hatched eaglet.
In 2010, the IUCN and BirdLife International listed this species as critically endangered. In 2015, about 600 were estimated to be left in the wild.
They 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, they are occasionally caught in traps laid by local people for deer.
The Philippine eagle has been featured on at least 12 stamps from the Philippines, with dates ranging from 1967 to 2007.
It was also depicted on the 50-centavo coins minted from 1981 to 1994.
The Philippine Eagle Foundation in Davao City, is one organization dedicated to the protection and conservation of the Philippine eagle and its forest habitat.
The Philippine Eagle Foundation has successfully bred Philippine eagles in captivity for over a decade and conducted the first experimental release of a captive-bred eagle to the wild.
The foundation has 36 eagles at its center, of which 19 were bred in captivity, including one born in 2015, the first for two years.

Music: Blue Macaw - Quincas Moreira (You Tube Audio Library)