The most powerful Forest Eagles
Conclusion based on the documented researched and data available:
The Philippine Monkey-eating eagles are opportunistic hunters/feeder, they take a variety of animals ranging in size from a small bat to a 14 kg or 30 lb deer, taking on what is most available and vulnerable, however food habits varies from Island to Island because of the different faunal composition and depending on seasons and availability of prey in the Islands/regions which the eagles inhabit.
COMPARISON OF PREY ITEMS of Philippine eagles and Harpy eagles:
These are the prey items found on different nests in Mindanao:
At various nests studied in Mindanao, 1977–1979,
flying lemurs were the principal food (54% of prey items), also palm civets Paradoxurus
hermaphroditus (12%), flying squirrels Petinomys (8%), fruit bats (genus Rousettus originally
given, but this doubted: N. R. Ingle in litt. 1997) (5%), monkeys (3%), plus a rat, a
30-pound
Philippine deer Cervus, a small bat (10–15g), an unidentified fledgling owl, two unidentified
hawks, Rufous Hornbills Buceros hydrocorax (6%), and several species of reptile (8%) including
snakes and a monitor lizard (Kennedy 1981b,c, 1983, 1985). However, at a nest in Aurora
province, October 1997, prey items seen comprised flying foxes Pteropus, macaques (Macaca Philippinensis)
and snakes (P. L. Alviola verbally 1997).
Source:
http://birdbase.hokkaido-ies.go.jp/rdb/rdb_en/pithjeff.pdf
And these are the Harpy Eagle’s documented prey items found at the nests:
Studies revealed that Harpies hunt atleast 19 species of mammals, 16 of which are tree dwelling. Sloths make up slightly more than a third of the diet and primates slightly less than a third. The eagles prey on animals as large as 11-lb red howler monkeys and even 17 lb two-toed sloths, creatures too heavy for the Harpy eagle to be carried whole. We recently found that Harpy eagles also feed on birds such as macaws, smaller parrots and gray-winged trumpeters, though these make up only about 5 % of the prey taken. Knowing what harpies eat could help determine the size and type of habitat preserve needed to safeguard the eagle population.
Source: National Geographic Magazine/February 1995 issue
Author: By NEIL RETTIG and KIM HAYES
FACTS
Predators tend to go for easy prey, so that they don’t use up too much energy in obtaining food and to avoid injuries.
Flying lemurs (Cynocephalus volans) are even harder to spot and catch than sloth, it could jump and glide from tree to tree and it’s capable to fly (glide) as far as 70 meters. So as the monkeys they are more agile and alert than sloth and heavier than the small monkeys (particularly those of the genus Chlorocebus), which the African crowned eagles hunts and
carries in flight.
http://www.youtube.com/watch?v=v9ENY2ujNUE The Philippine long-tailed macaques (mcaca philippinensis) weigh 4-6 kg and large males can weigh up to 9 kg.
Largest prey item found at one of the nest - a 30 lb deer cervus.
Based on the documented prey items above, It shows that the Philippine monkey-eating eagle is truly a powerful eagle perhaps even more powerful than the Harpy eagle coz’ it can carry heavier load of prey than those two forests eagles. It has the largest wing surface area among all the living eagles capable of more powerful lift. Dub as “ One of the largest and most powerful birds on earth.” And this only proves that the way it looks is not a misconception.
ATB
Blubeak
One of the largest powerful bill and longest eagle's legs and claws.