Location and General Description
This ecoregion represents the moist forests in the island of Buru. Based on the Köppen climate zone system, this ecoregion falls in the tropical wet climate zone (National Geographic Society 1999). Buru is part remnant crustal fragment, probably from the Australian continent, and part of the volcanic Inner Banda Arc. Consequently, the surface geology of Buru is complex, consisting of older metamorphic schists and gneiss, younger volcanics, and recent alluvium (Monk et al. 1997).
The natural vegetation of the island was tropical lowland evergreen and semi-evergreen rain forests (Stattersfield et al. 1998). The dominant tree species in this moist forest are the dipterocarps, Anisoptera thurifera, Hopea gregaria, H. iriana, H. novoguineensis, Shorea assamica, S. montigena, S. selanica, and Vatica rassak (Monk et al. 1997). In old-growth forests, the larger trees grow to more than 30 m in height and tend to be covered with thick-stemmed lianas and other epiphytes. Open forest, woodland, and savanna are also found in this ecoregion, with some being natural but most originating from human activity (Flannery 1995). The fire-resistant paper bark tree (Melaleuca cajuputi) is common and grows in nearly monotypic stands in dry areas (Whitten and Whitten 1992). The steep limestone cliffs in the northwestern part of the ecoregion are covered by mixed forests that include Shorea spp. (Monk et al. 1997). Exposed ridges between 1,800 and 2,000 m above sea level are characterized by stunted Dacrydium novo-guineense (Monk et al. 1997).
Overall richness and endemism in this ecoregion are low to moderate when compared with those of other ecoregions in Indo-Malaysia. Being in the Wallacean biogeographic zone, the ecoregion contains a mixture of Asian and Australian fauna. The mountainous areas of this island are largely unexplored and may contain many undiscovered species (Flannery 1995).
The known mammal fauna of Buru consists of at least twenty-five species, including four near endemics (table 1). Two of these species are globally threatened: the vulnerable Seram flying-fox (Pteropus ocularis) and lesser tube-nosed fruit bat (Nyctimene minutus) (IUCN 2000).
Table 1. Endemic and Near-Endemic Mammal Species.
Pteropodidae Pteropus chrysoproctus
Pteropodidae Pteropus ocularis
Pteropodidae Nyctimene minutus
Suidae Babyrousa babyrussa
An asterisk signifies that the species' range is limited to this ecoregion.
The bird fauna consists of 178 species, including twenty-nine endemic or near-endemic species (table 2). The ecoregion corresponds with the Buru EBA and contains twenty-eight restricted-range bird species, ten of which are found nowhere else on Earth. Six of these species are considered vulnerable: Moluccan scrubfowl (Megapodius wallacei), blue-fronted lorikeet (Charmosyna toxopei), black-lored parrot (Tanygnathus gramineus), Buru cuckoo-shrike (Coracina fortis), streaky-breasted jungle-flycatcher (Rhinomyias addita), and rufous-throated white-eye (Madanga ruficollis), which represents a monotypic genus (Stattersfield et al. 1998).
Table 2. Endemic and Near-Endemic Bird Species.
Family Common Name Species
Accipitridae Rufous-necked sparrowhawk Accipiter erythrauchen
Megapodiidae Forsten's scrubfowl Megapodius forstenii
Megapodiidae Moluccan scrubfowl Megapodius wallacei
Columbidae White-eyed imperial-pigeon Ducula perspicillata
Columbidae Long-tailed mountain-pigeon Gymnophaps mada
Psittacidae Buru racquet-tail Prioniturus mada*
Psittacidae Black-lored parrot Tanygnathus gramineus*
Loriidae Red lory Eos bornea
Loriidae Blue-fronted lorikeet Charmosyna toxopei*
Strigidae Moluccan hawk-owl Ninox squamipila
Tytonidae Lesser masked-owl Tyto sororcula
Meliphagidae Buru honeyeater Lichmera deningeri*
Meliphagidae Wakolo myzomela Myzomela wakoloensis
Meliphagidae Black-faced friarbird Philemon moluccensis
Pachycephalida Drab whistler Pachycephala griseonota
Rhipiduridae Cinnamon-backed fantail Rhipidura superflua*
Monarchidae White-naped monarch Monarcha pileatus
Monarchidae Black-tipped monarch Monarcha loricatus*
Monarchidae Moluccan flycatcher Myiagra galeata
Oriolidae Buru oriole Oriolus bouroensis
Campephagidae Buru cuckoo-shrike Coracina fortis*
Campephagidae Pale-grey cuckoo-shrike Coracina ceramensis
Turdidae Moluccan thrush Zoothera dumasi
Muscicapidae Streaky-breasted jungle-flycatcher Rhinomyias addita*
Muscicapidae Cinnamon-chested flycatcher Ficedula buruensis
Zosteropidae Buru white-eye Zosterops buruensis*
Zosteropidae Rufous-throated white-eye Madanga ruficollis*
Sylviidae Chestnut-backed bush-warbler Bradypterus castaneus
Dicaeidae Flame-breasted flowerpecker Dicaeum erythrothorax
An asterisk signifies that the species' range is limited to this ecoregion.
Buru's butterflies include a large number of endemics and are therefore accorded highest conservation priority. Pifridae has 25 percent of the local species unique to Buru, and Papilionidae 7 percent (Vane-Wright and Peggae, in press).
The coastal lowland forests have been cleared, and the northern and northeastern portions of the island now contain monsoon forest, gallery forest, and savannas as a result of repeated burning (Stattersfield et al. 1998). However, the remaining upland forest forms two large, contiguous blocks. Most of this forest is a mosaic of primary and secondary forest as a result of shifting cultivation (Monk 1997; Stattersfield et al. 1998).
The two protected areas-of which one is greater than 1,000 km2-cover 17 percent of the ecoregion (table 3). Commercial logging on Buru intensified during the 1970s, but much of the island is still under extensive forest cover.
Table 3. WCMC (1997) Protected Areas That Overlap with the Ecoregion.
Protected Area Area (km2) IUCN Category
Gunung Kelpat Muda 1,380 PRO
Waeapo 50 PRO
Ecoregion numbers of protected areas that overlap with additional ecoregions are listed in brackets.
Types and Severity of Threats
Current threats to this ecoregion are low, causing its conservation status to remain vulnerable. Commercial logging and shifting cultivation are the primary threats to the remaining habitat.
Justification of Ecoregion Delineation
The Sula Islands were included within the Sulawesi Lowland Rain Forests [AA0123] and the Aru Islands in the Vogelkop-Aru Lowland Rain Forests [AA0128]. Buru Island, identified as a distinct subunit (13c) by MacKinnon (1997) and as an EBA (Stattersfield et al. 1998), was delineated as a distinct ecoregion, the Buru Rain Forests [AA0104]. Seram, the larger island to the east of Buru, was also delineated as an ecoregion: Seram Rain Forests [AA0118]. The larger Halmahera Rain Forests [AA0106] includes Obi Island, which MacKinnon (1997) recognized as a separate subunit (13b) from Halmahera Island (subunit 13a). We created the Banda Sea Islands Moist Deciduous Forests [AA0102] by combining the islands in the Kai and Tanimbar archipelagos, which Monk et al. (1997) distinguished as a biogeographic unit. The primary vegetation on the islands in both these archipelagos is moist deciduous forests and semi-evergreen forests, whereas the vegetation in the other, nearby large islands (Seram and Aru) is evergreen rain forests (Monk et al. 1997).
References for this ecoregion are currently consolidated in one document for the entire Indo-Pacific realm.
Indo-Pacific Reference List
Prepared by: John Morrison
This text was originally published in the book Terrestrial ecoregions of the Indo-Pacific: a conservation assessment from Island Press. This assessment offers an in-depth analysis of the biodiversity and conservation status of the Indo-Pacific's ecoregions.