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Javan hawk-eagle (Nisaetus bartelsi)

The Javan hawk-eagle or Javanese eagle or Elang Jawa (Nisaetus bartelsi) is one of the endemic eagle species on Mount Merapi, medium to large, and slim with a length of up to 70 cm. The reddish-brown head (cadre) has a crest of 2 to 4 feathers for up to 12 cm long and a yellowish brown neck.

Black crested with white ends, black crown and mustache, while back and wings are dark brown. The esophagus is whitish with a long black line in the middle. The chest has black streaks spread over the brownish yellow which eventually turn into a dense line pattern and red transverse above the whitish color of the abdominal and leg feathers.

Dlium Javan hawk-eagle (Nisaetus bartelsi)


Feathers cover the legs to close to the base of the finger. A brownish tail with four dark lines and a wide cross is clearly visible on the lower side, and the tip of the tail is thin white striped. Females are similar in color, but have a slightly larger size.

The iris is yellow and brownish, half-black, sera yellowish, and yellowish legs. Young birds have a head, neck and lower body with brown wood and without streaks or lines.

Javanese eagles fly and shout loud and repetitive sounds, like klii-iiw, which vary from one to three syllables. High and fast pitched sounds like kli-kli-kli-kli-kli. This sound is similar to Spizaetus cirrhatus, although it has clear differences in tone.

The distribution of these eagles is limited to Java and only in primary forests in the transition from the lowlands to the mountains. Most are found in half the southern hemisphere of Java where these birds live specializing in sloping areas, but have cruises to the coast in the lowlands and up to 3,000 meters above sea level.



Eagle is one of the top predators in the food chain cycle of a forest ecosystem. This bird hunts from a place perched on tall trees in the forest to glide and ambush reptiles, birds, pigs, native chickens, squirrels, bats, civets, and monkeys.

The laying period begins in January to June in a pile of leafy branches arranged in trees as high as 20-30 meters. Only one egg and was incubated for 47 days. Nests are generally in Rasamala (Altingia excelsa), pairs (Lithocarpus sundaicus), tusam (Pinus merkusii), puspa (Schima wallichii), and ki sireum (Eugenia clavimyrtus).

Dlium.com Javan hawk-eagle (Nisaetus bartelsi)


Javanese eagle was known in 1820 when van Hasselt and Kuhl collected two specimens for the Leiden Museum, but until the end of the 19th century it was still considered as Spizaetus. The IUCN included Javanese eagles in the status of EN (Endangered) and the Indonesian Government designated them as animals protected by law.

The bird monitoring team at the Mount Merapi National Park Center conducted regular observations on eagles and other raptor to monitor this bird on Mount Merapi. Javanese eagles are less competitive than Black Hawk (Ictinaetus malayensis) and Bido Eagle (Spilornis cheela), also by habitat degradation.



Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Accipitriformes
Family: Accipitridae
Genus: Nisaetus
Species: N. bartelsi

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