Justification The population of this impressive raptor is very small. Moreover, given the destruction, disturbance and degradation that is currently being inflicted on its preferred habitat, it is likely to be declining and increasingly fragmented, a circumstance that qualifies it as Endangered.

Family/Sub-family Accipitridae

Species name author Stresemann, 1924

Taxonomic source(s) Sibley and Monroe (1990, 1993)

Identification 60 cm. Medium-sized, forest-dwelling eagle. Crown and moustachial of adult are black, long crest (often held almost vertically) is black, tipped white. Chestnut sides of head and nape, dark brown back and wings, brown long tail, barred black. Creamy-white throat with dark mesial stripe. Rest of underparts whitish, barred rufous. Immature is similar, but with plainer underparts and duller head. Similar spp. Changeable Hawk-eagle Spizaetus cirrhatus lacks rufous cheeks and long crest. Crested Honey-buzzard Pernis ptilorhynchus is smaller with a shorter crest, uneven tail-barring and less rufous in plumage. Rufous-bellied Eagle Hieraaetus kienerii has shorter crest and extensive white upper breast streaked black.

Population estimate

Population trend

Range estimate (breeding/resident)

Country endemic?

600 - 900

decreasing

14,500 km²

Yes

Range & population Spizaetus bartelsi is endemic to the island of Java, Indonesia, where it is restricted to remaining patches of forest and is consequently scarce. An increase in survey effort and knowledge of the species's home-range size has led to consecutive upward revisions of the global population, now estimated at over 600 individuals⁴ (with one estimate of 270-600 pairs²). It is distributed widely throughout much of the island with a recent increase in the number of known localities, though it remains unrecorded from large areas of the north. Although there is no direct indication of a decline, the ongoing diminution of forest-cover on Java is certain to have been detrimental.

Important Bird Areas Click here to view map showing IBAs where species is recorded and triggers any of the IBA criteria.

Ecology: It frequents primary humid forest, although individuals and even nests have been recorded in secondary forest, production forest and tropical semi-deciduous forest. While it occurs from sea-level to high mountains, it is most frequent at 500-1,000 m. Recent extensive research has estimated the average home range size of one pair to be c. 400 ha². The species's dispersal capabilities (and therefore its susceptibility to habitat fragmentation) remain poorly known, but adults appear to be highly sedentary while young birds are the main dispersers³. Juveniles and immatures are recorded in woodland and some cultivated habitats before moving to secondary and primary evergreen forest as adults³; this behaviour suggests that unsuitable habitats may not represent barriers to dispersal. It breeds every two years, principally between January and July, but can breed at any time of year¹. The preferred diet consists of small mammals but it will take birds, snakes and lizards¹.

Threats The key threats are habitat loss and trade. The burgeoning human population on Java brings with it intense pressure on natural resources, one aspect of which has been a massive reduction in forest cover, particularly in the lowlands. This threat continues in the form of conversion to agriculture, development and uncontrolled fire, even within protected areas. The species is also sold openly in Javan bird markets, with 30-40 reported in trade each year, and presumably many more undetected. This threat appears to be intensifying, following the elevation of the species to national bird.

Conservation measures underway CITES Appendix II. Several surveys have targeted the species, exploring its distribution and ecology¹. Strict legislation protects it from hunting or trading, although this is often ineffective. It occurs in several protected areas, including Gunung Halimun, Gunung Gede-Pangrango and Meru Betiri National Parks, although these still face serious problems. An action plan has been compiled and conservation awareness programmes including several training and awareness raising workshops have been initiated^1,5. Project Garuda run in 2002-2003 in Butahu, West Java combined research with conservation activities implementing an extensive awareness raising programme including radio broadcasts, school visits and an exhibition⁵. A nest protection programme involving local communities has been run successfully¹. Regular monitoring occurs in Telaga Warner Nature Reserve, Gede-Pangrango National Park and parts of G. Halimum-Salak National Park¹ and surveys took place around Butahu from 2002-2003⁵.

Conservation measures proposed Implement the Javan Hawk-eagle Recovery Plan. Continue ecological studies to allow appropriate management regimes to be devised. Improve management of existing protected areas, and establish further reserves, particularly in central Java, at Dieng Mountains and Gunung Slamet, and West Java in southern Cianjur district. Continue to search for and guard nests found near human populations. Improve and enforce legislation to control trade. Continue and expand education schemes to elicit public support for the conservation of this and other threatened species on Java.

References BirdLife International (2001). 1. Prawiradilaga (2006). 2. Gjershaug et al. (2004). 3. Nijman and van Balen (2003). 4. Prawiradilaga (2004). 5. Narwatha et al. (2007).

Further web sources of information

Fully detailed species accounts from the Threatened birds of Asia: the BirdLife International Red Data Book (BirdLife International 2001), together with new information collated since the publication of the Red Data Book

Text account compilers Phil Benstead (BirdLife International), Jeremy Bird (BirdLife International), Joe Tobias (BirdLife International)

IUCN Red List evaluators Jeremy Bird (BirdLife International), Stuart Butchart (BirdLife International)

Recommended citation BirdLife International (2009) Species factsheet: Spizaetus bartelsi. Downloaded from http://www.birdlife.org on 9/2/2010

This information is based upon, and updates, the information published in BirdLife International (2000) Threatened birds of the world. Barcelona and Cambridge, UK: Lynx Edicions and BirdLife International, BirdLife International (2004) Threatened birds of the world 2004 CD-ROM and BirdLife International (2008) Threatened birds of the world 2008 CD-ROM. These sources provide the information for species accounts for the birds on the IUCN Red List.

To provide new information to update this factsheet or to correct any errors, please email BirdLife

To contribute to discussions on the evaluation of the IUCN Red List status of Globally Threatened Birds, please visit BirdLife's Globally Threatened Bird Forums