Philippine Eagle

About

The Philippine Eagle, also known as the Monkey-eating Eagle, is one of the largest and most powerful eagles in the world. It is endemic to the Philippines and is critically endangered. It is characterized by its shaggy crest, large hooked beak, and powerful talons, adapted for hunting arboreal prey.

Size & lifespan

Length

86-102 cm (34-40 in)

Wingspan

184-220 cm (6 ft 0 in - 7 ft 3 in)

Weight

4.7-8.0 kg (10.4-17.6 lb), with females generally larger than males

Lifespan

Up to 30-60 years in captivity; less in the wild, likely 15-25 years.

Diet

Primarily arboreal and ground mammals (e.g., flying lemurs, civets, monkeys, bats, squirrels) and large birds (e.g., hornbills). Snakes and monitor lizards are also taken.

Physical characteristics

Plumage

Adults have a dark brown back and wings, with a creamy-white belly and underwing coverts. The most distinctive feature is a shaggy, long crest of narrow brown feathers on the head and nape, giving the head a lion-like or bushy appearance. The crown feathers are lighter brown with darker shaft streaks. The underparts are white to creamy. Juveniles are similar but with more mottled brown on the back and a less developed crest.

Beak shape

Large, deep, and prominently hooked, dark grey to black.

Eye color

Grey-blue in juveniles, changing to pale blue-grey in adults.

Leg color

Bright yellow, with powerful black talons.

Distinguishing features

Massive size, shaggy crest, dark brown upperparts contrasting with creamy-white underparts, and powerful yellow legs with enormous talons.

Juvenile appearance

Juveniles have a similar overall pattern but are generally lighter brown on the upperparts with pale feather edgings, appearing more scaled. The head crest is shorter and less developed, and the underparts may have some buffy wash. Their eyes are grey-blue, transitioning to adult coloration.

Seasonal changes

No significant seasonal changes in plumage.

Sexual dimorphism

Females are typically 10-20% larger than males in weight and wing-length, though plumage is similar. This size difference is less pronounced in overall length than in some other raptor species.

How to identify

1. 1

   Size

   Its immense size, making it one of the largest eagles in the world, is often the first clue. It appears truly massive, even at a distance.

2. 2

   Head and Crest

   The prominent, shaggy crest of long, narrow brown feathers on its head and nape is unique among raptors in its range.

3. 3

   Plumage Contrast

   The stark contrast between its dark brown upperparts and creamy-white underparts is a key field mark.

4. 4

   Beak and Talons

   Its enormous, deep, dark hooked beak and powerful yellow legs with huge black talons are indicative of its predatory power and further distinguish it.

5. 5

   Flight Profile

   In flight, its massive broad wings, slightly rounded tail, and often prominent head and crest can be discerned.

6. 6

   Vocalization

   Its loud, high-pitched whistling calls, though generally heard infrequently, are distinctive.

Habitat & range

Biomes

Tropical and subtropical moist broadleaf forests.

Geographic range

Endemic to the Philippines, primarily found on four major islands: Luzon, Samar, Leyte, and Mindanao. The largest remaining populations are on Mindanao and Luzon.

Elevation range

Typically found from lowlands up to 1,800 meters (5,900 feet) in undisturbed primary and old-growth forests.

Preferred environments

Dense, old-growth rainforests with tall emergent trees for nesting and perching. Requires extensive forest cover and a continuous canopy for hunting.

Behavior

Activity time

Diurnal, active during daylight hours.

Feeding habits

A highly specialized predator, often hunting from a high perch, swooping down to snatch prey from trees or the forest floor. They are also known to hunt in pairs, with one bird distracting prey while the other attacks. They are known for their powerful grip and sharp talons, capable of killing relatively large prey.

Social behavior

Generally solitary or in breeding pairs. Very territorial, with pairs maintaining large home ranges. Interactions outside of breeding pairs are rare.

Flight pattern

Powerful and agile in flight despite its size. Exhibits soaring flight high above the forest canopy on broad wings, but also capable of maneuvering through dense forest. Often seen perching prominently on tall snag trees.

Migration pattern

Sedentary; non-migratory.

Territoriality

Highly territorial. Breeding pairs defend large territories, sometimes up to 100 square kilometers, which are crucial for finding sufficient prey to support their long breeding cycle.

Breeding & reproduction

Breeding season

Breeding can occur year-round, but peaks from July to February, varying slightly by island. The breeding cycle is one of the longest among raptors.

Nesting habits

Builds massive nests, up to 1.5 meters (5 feet) across and 30 meters (100 feet) deep, usually in the fork of a tall, emergent forest tree (often a 'Toog' tree, Koompassia excelsa). Nests are reused across multiple breeding seasons.

Clutch size

One egg, rarely two.

Egg description

Typically a single, dull white egg.

Incubation period

Approximately 58-62 days, primarily by the female, though the male assists in foraging and occasionally incubating.

Fledging period

The chick fledges at around 130-150 days (4-5 months) after hatching. Post-fledging parental care continues for an extended period, often up to 18-20 months, making the breeding cycle often two years long.

Parental care

Both parents are involved in raising the single chick. The male provides most of the food during incubation and early chick rearing, while the female guards the nest. Parental care is prolonged, with juveniles staying with parents for a lengthy period, learning hunting skills.

Where to find

Field tips

1. Hire Local Guides. Engage experienced local bird guides who are familiar with the eagle's territory and habits. Their knowledge is invaluable for locating these elusive birds.
2. Patience and Persistence. Spotting a Philippine Eagle in the wild requires significant patience. Be prepared for long periods of waiting and multiple attempts. Success is not guaranteed due to their rarity and preferred dense habitat.
3. Look for Soaring Birds. Scan the skies above suitable forest habitats, especially during mid-morning to early afternoon, when they may be soaring on thermals.
4. Listen for Calls. Be attentive to their distinctive calls, which can sometimes lead you to their general vicinity, particularly during morning or late afternoon.
5. Look for Perches. They often perch on prominent, tall emergent trees that rise above the forest canopy. Focus your search on such potential perching sites.
6. Support Conservation. Consider visiting and supporting the Philippine Eagle Center and other conservation initiatives, as their work is vital for the species' survival.

Similar species

Quick facts

National Bird:

It is the national bird of the Philippines.

Monogamous:

Breeding pairs are monogamous and mate for life.

Largest Forest Raptor:

Considered the largest extant forest raptor in terms of length and wing surface area.

Iconic Species:

A symbol of Philippine biodiversity and conservation efforts.

Long Breeding Cycle:

Has one of the longest breeding cycles of any bird of prey, often taking two years to fledge a single chick to independence.

Fun facts

• Its former common name 'Monkey-eating Eagle' was somewhat misleading, as monkeys make up only a small part of its diet. Flying lemurs (colugos) are a much more significant prey item.
• The scientific name 'Pithecophaga jefferyi' means 'monkey-eating' (Pithecophaga) and honors the father of the discoverer, W.R.B. Jeffery, who sent the specimen to England.
• A substantial fine and up to 12 years in prison is the penalty for killing a Philippine Eagle in the Philippines.
• It requires vast tracts of untouched primary forest, which illustrates its role as an umbrella species for the conservation of Philippine rainforests.

Scientific classification

Kingdom

Animalia

Phylum

Chordata

Class

Aves

Order

Accipitriformes

Family

Accipitridae

Genus

Pithecophaga

Species

jefferyi

Explore the Philippine Eagle