|Population||250-750 (2003 est.)|
|Conservation status||Critically endangered|
The Philippine eagle (Pithecophaga jefferyi) is a rare bird native to several islands of the Philippines archipelago, and is the national emblem of that country. Among the largest and most powerful of eagles, the Philippine eagle has suffered in recent decades due to loss of habitat and hunting.
The Philippine eagle female is approximately 3.3 feet long from beak to tail tip, with some specimens in museums a few inches longer. Its wingspan is from 6 to 6.5 feet, and it weighs up to 18 pounds. Males are about 10% smaller.
It is colored a dark, chocolate brown above, with its wing feathers tinged in a pale cream; below the eagle is mainly white. The head and top of the neck is adorned with a brown-streaked crest, giving the bird a regal appearance when erect, and possibly inspiring the Tagalog name "Haring Ibon" ("bird king"). The beak is deep, laterally-compressed and massive. It is also blue-gray in color, the only eagle to have this distinction.
The plumage of young birds differ only slightly from that of the adults. The light tinges of the upper plumage are usually wider and more white than in adult birds. The iris is brown and the legs are a lighter, more whitish yellow. At what age the juveniles take on the adult plumage is not yet known.
The calls are described as strange-sounding whining or as long, soft or high whistles like "whiiiiiiuh", which usually rise in pitch, but occasionally fall off. Males are quite vociferous during courtship. Begging young birds express a conspicuous and far-reaching series of high and pointed calls.
The first specimen of the Philippine Eagle was collected by John Whitehead in 1896 on Samar, who was told by the natives there that it fed exclusively on monkeys alone; the first describers of this bird to Western science would be influenced by this description of its eating habit and give it the name Pithecophaga (Greek: πίθηκος, píthēkos: "monkey"; and φᾰγεῖν, phagein: "eating"), "eater of monkeys". Until a presidential decree in 1978 officially changing its name, it was previously known - rather inaccurately as well as disrespectfully - as the monkey-eating eagle.
Due to similarities in size and behavior the Philippine eagle has long been placed together in a subfamily named Harpiinae with several neotropical species, among them the harpy eagle (Harpia harpyja), the crested eagle (Morphnus guianensis), both of South America, and the New Guinea harpy eagle (Harpyopsis novaeguineae). However, according to molecular genetic studies, the Philippine eagle is not closely related to these three species, but to the subfamily Circaetinae, which includes the snake or serpent eagles of the genera Circaetus, Spilornis, and Terathopius.
Range and habitat
The Philippine eagle is endemic to the Philippines and is found on four islands: eastern Luzon, Samar, Leyte and Mindanao. The total size of its range is estimated at about 56,370 square miles. Whether it used to occur in the entire Philippines or has always been absent in the drier west of the archipelago is unclear. Philippine eagles live in primary rainforests, especially in mountainous terrain, secondary forests and gallery forests. The species occurs at altitudes from 0 to 5,400 feet.
On Mindanao relatively uniform distances of 5-10 miles were found in the 1990s between 14 neighboring areas, with an average of 7 miles. The authors assume that a circle with a radius of one-half of this distance might be about the size of a territory for a pair, which has an average size of 51.3 sq mi. On average, 28.1 sq mi of forest were located in this calculated area, with the rest consisting of open land with different uses. Of the 13 nests found, nine were less than 300 feet from the edge of the forest. The other four were further away from the edge of the forest, but the associated spaces still contained a significant proportion of open land. Whether it is possible to derive a preference for forest edge areas from these findings is uncertain. It is also possible that the nests there are only easier to find or that this distribution is enforced by the strong fragmentation of the remaining forest areas.
The Philippine eagle feeds upon a variety of animals: snakes and lizards; birds; flying lemurs; palm civets; and the occasional domestic dog; it has been known to get any animal it could kill when the opportunity presents. Monkeys are also part of the diet, when and where the eagle can get them.
Philippine eagle pairs mate for life, and only mate with another when a partner dies. A single egg is laid in a large nest constructed in a treetop at or near a forest edge, and is incubated for about 60 days. The nesting period can last nearly four months, as both parents take turns feeding the chick, which won't begin to fend for itself until at least its fourth month after leaving the nest. The eagle has been known to live up to 40 years in captivity.
The Philippine eagle is listed as critically endangered by the IUCN Red List; the four islands which still support populations of these eagles (Luzon, Samar, Leyte and Mindanao) report approximately 300 breeding pairs, with the bulk of the pairs on Mindanao (82-233 pairs). Deforestation continues to occur within these islands, reducing the bird's range and food availability. Sporadic hunting has also taken a toll, despite laws on the books resulting in heavy fines and long prison sentences for killing one.