Southeastern Asia: Extends across central New Guin

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The Central Range Montane Rain Forests [AA0105], which form the mountain spine of the island of New Guinea, contain more than 100 endemic vertebrates. The Central Ranges separate adjoining lowland on each side of the cordillera, and several constituent mountain ranges are isolated such that an extraordinary level of speciation has occurred within the Central Ranges. Some species are shared with outlying mountain ranges, but there are a significant number of locally endemic plants that are known only from a single mountain or mountain range (R. Johns, pers. comm., 2000).

  • Scientific Code
  • Ecoregion Category
  • Size
    66,400 square miles
  • Status
    Relatively Stable/Intact
  • Habitats

Location and General Description
This ecoregion is made up of the montane forests between 1,000 m and 3,000 m in the Central Cordillera of the island of New Guinea, in Irian Jaya, Indonesia and PNG, in the western Pacific Ocean north of Australia. The Central Cordillera is composed of a series of mountain ranges that are broadly grouped into the Snow Mountains in Irian Jaya, the Star Mountains in Irian Jaya and PNG, and the Central and Eastern Highlands in PNG. The climate of the ecoregion is tropical highland wet because of its elevation (National Geographic Society 1999). The surface geology of the Central Cordillera is composed of metamorphic and intrusive igneous rocks (Bleeker 1983). The metamorphic rocks were Cretaceous (100 m.y.) and Eocene (40 m.y.) ocean sediments that were folded between the Eocene and early Miocene Periods (20 m.y.) (Petocz 1989). Pleistocene stratovolcanoes are also found in the Central Ranges (Bleeker 1983).

There are three broad vegetation zones in the Central Ranges: lower montane forest, upper montane forest, and high mountain forest (although these are sometimes lumped into one lower montane rain forest; see Davis et al. 1995). Lower montane forest continues up from the lowlands to approximately 2,500 m. This zone is dominated by oaks, such as Castanopsis acuminatissima, elaeocarps, and laurels. Araucaria may form thick stands in lower areas. Nothofagus, sometimes in monotypic stands, is conspicuous in the moss-covered upper montane forest, which begins at about 1,500 m. High mountain forest begins at approximately 2,500 m and continues past the upper limits of the ecoregion, to 3,900 m. The species-poor, high mountain forest includes conifers (Podocarpus, Dacrycarpus, Dacridium, Papuacedrus, Araucaria, and Libocedrus) and Myrtacae, with a thin canopy and prominent understory (Beehler et al. 1986; Davis et al. 1995; FAO 1981; Petocz 1989; Stattersfield et al. 1998).

Biodiversity Features
The overall richness of this ecoregion is remarkable and ranges from moderate to high. The ecoregion contains some of the highest richness of vascular plants and herpetofauna in Indo-Malaysia and some of the highest endemism for mammals, birds, and vascular plants.

The mammalian fauna consists of a wide variety of tropical Australasian marsupials, including tree kangaroos (Flannery 1995). Ninety mammal species inhabit this ecoregion, of which an incredible forty-four are endemic or near endemic (Flannery 1995; Flannery and Groves 1998; Bonaccorso et al., in press) (table 1). Four of these species are considered critically endangered: Bulmer's fruit-bat (Aproteles bulmerae), large leptomys (Leptomys elegans), eastern shrew-mouse (Pseudohydromys murinus), and lesser small-toothed rat (Macruromys elegans) (IUCN 2000).

Table 1. Endemic and Near-Endemic Mammal Species.

Family Species
Dasyuridae Neophascogale lorentzi*
Dasyuridae Phascolosorex doriae
Dasyuridae Antechinus wilhelmina
Phalangeridae Phalanger vestitus*
Phalangeridae Phalanger matanim*
Macropodidae Dorcopsulus macleayi
Pseudocheiridae Pseudocheirus caroli*
Pseudocheiridae Pseudocheirus mayeri*
Petauridae Dactylopsila megalura*
Peroryctidae Microperoryctes murina
Peroryctidae Echymipera clara
Pteropodidae Aproteles bulmerae
Pteropodidae Syconycteris hobbit
Emballonuridae Emballonura furax
Rhinolophidae Hipposideros corynophyll*
Rhinolophidae Hipposideros muscinus
Vespertilionidae Pipistrellus collinus
Vespertilionidae Nyctophilus microdon*
Vespertilionidae Kerivoula muscina
Molossidae Otomops secundus
Muridae Leptomys elegans
Muridae Paraleptomys wilhelmina*
Muridae Neohydromys fuscus
Muridae Pseudohydromys murinus
Muridae Mayermys ellermani
Muridae Hydromys hussoni
Muridae Hydromys habbema*
Muridae Crossomys moncktoni
Muridae Macruromys elegans*
Muridae Xenuromys barbatus
Muridae Melomys fellowsi*
Muridae Melomys lorentzi
Muridae Melomys lanosus*
Muridae Pogonomelomys mayeri
Muridae Pogonomelomys bruijni
Muridae Abeomelomys sevia
Muridae Coccymys albidens*
Muridae Rattus giluwensis*
Muridae Rattus novaeguineae
Muridae Hyomys dammermani
Muridae Hydromys shawmayeri
Muridae Leptomys ernstmayeri
Muridae Melomys gracilis
Muridae Pogonomys championi*

An asterisk signifies that the species' range is limited to this ecoregion.

The avifauna of the ecoregion has a clear Australasian flavor, including representatives of several Australasian families such as Ptilonorhynchidae, Eopsaltridae, Meliphagidae, and Paradisaeidae. The ecoregion harbors 348 bird species, of which 55 are endemic or near endemic (table 2). This ecoregion forms the majority of the Central Papuan mountains EBA, which contains fifty-three restricted-range bird species, eight of which are found in the adjacent Central Range sub-alpine grasslands, thirteen of which are shared with the adjacent Central Range sub-alpine grasslands, and seventeen of which are found nowhere else on Earth. Four of these species represent endemic genera (Stattersfield et al. 1998; Beehler et al. 1986; Coates 1985). Archbold's bowerbird (Archboldia papuensis), ribbon-tailed astrapia (Astrapia mayeri), and the blue bird-of-paradise (Paradisaea rudolphi) are considered vulnerable (IUCN 2000).

Table 2. Endemic and Near-Endemic Bird Species.

Family Common Name Species
Rallidae Chestnut forest-rail Rallina rubra
Loriidae Orange-billed lorikeet Neopsittacus pullicauda
Loriidae Striated lorikeet Charmosyna multistriata
Psittacidae Painted tiger-parrot Psittacella picta
Psittacidae Madarasz's tiger-parrot Psittacella madaraszi
Psittacidae Modest tiger-parrot Psittacella modesta
Aegothelidae Archbold's owlet-nightjar Aegotheles archboldi
Caprimulgidae Mountain eared-nightjar Eurostopodus archboldi
Apodidae Bare-legged swiftlet Aerodramus nuditarsus
Apodidae Papuan swiftlet Aerodramus papuensis
Campephagidae Hooded cuckoo-shrike Coracina longicauda
Acanthizidae Papuan thornbill Acanthiza murina
Cinclosomatidae Blue-capped ifrita Ifrita kowaldi
Cinclosomatidae Papuan whipbird Androphobus viridis*
Melanocharitidae Streaked berrypecker Melanocharis striativentris
Eopsaltriidae White-winged robin Peneothello sigillatus
Eopsaltriidae Green-backed robin Pachycephalopsis hattamensis
Eopsaltriidae Greater ground-robin Amalocichla sclateriana
Eopsaltriidae Alpine robin Petroica bivittata
Eopsaltriidae Smoky robin Peneothello cryptoleucus
Pachycephalidae Sooty shrike-thrush Colluricincla umbrina*
Pachycephalidae Lorentz's whistler Pachycephala lorentzi
Pachycephalidae Wattled ploughbill Eulacestoma nigropectus
Pachycephalidae Black sittella Daphoenositta miranda
Climacteridae Papuan treecreeper Cormobates placens
Meliphagidae Orange-cheeked honeyeater Oreornis chrysogenys
Meliphagidae Leaden honeyeater Ptiloprora plumbea
Meliphagidae Rufous-sided honeyeater Ptiloprora erythropleura
Meliphagidae Black-backed honeyeater Ptiloprora perstriata
Meliphagidae Spot-breasted meliphaga Meliphaga mimikae
Meliphagidae Olive-streaked honeyeater Ptiloprora meekiana
Meliphagidae Yellow-browed honeyeater Melidectes rufocrissalis
Meliphagidae Sooty honeyeater Melidectes fuscus
Meliphagidae Belford's honeyeater Melidectes belfordi
Meliphagidae Rufous-backed honeyeater Ptiloprora guisei
Meliphagidae Cinnamon-browed honeyeater Melidectes ochromelas
Estrildidae Snow Mountain munia Lonchura montana*
Estrildidae Black-breasted munia Lonchura teerinki*
Estrildidae Mountain firetail Oreostruthus fuliginosus
Ptilonorhynchidae Archbold's bowerbird Archboldia papuensis*
Paradisaeidae Short-tailed paradigalla Paradigalla brevicauda*
Paradisaeidae King-of-Saxony bird-of-paradise Pteridophora alberti*
Paradisaeidae Yellow-breasted bird-of-paradise Loboparadisea sericea
Paradisaeidae Loria's bird-of-paradise Cnemophilus loriae
Paradisaeidae Long-tailed paradigalla Paradigalla carunculata
Paradisaeidae Carola's parotia Parotia carolae
Paradisaeidae Lawes's parotia Parotia lawesii
Paradisaeidae Splendid astrapia Astrapia splendidissima
Paradisaeidae Ribbon-tailed astrapia Astrapia mayeri
Paradisaeidae Blue bird-of-paradise Paradisaea rudolphi
Paradisaeidae Crested bird-of-paradise Cnemophilus macgregorii
Paradisaeidae MacGregor's bird-of-paradise Macgregoria pulchra
Paradisaeidae Brown sicklebill Epimachus meyeri
Paradisaeidae Princess Stephanie's astrapia Astrapia stephaniae
Paradisaeidae Greater melampitta Melampitta gigantea

An asterisk signifies that the species' range is limited to this ecoregion.

Within this ecoregion, the Weyland Range (with nine endemic species) and the Hagen-Sepik-Wahgi Divide (with five endemic species) are both centers of butterfly endemism on the island of New Guinea (Parsons 1999).

Seven Centres of Plant Diversity are shared between this ecoregion and the adjacent Central Ranges sub-alpine grassland ecoregion. The Star Mountains-Telefomin-Tifalmin-Strickland Gorge CPD in PNG contains very rich (more than 3,000 vascular plant species) montane and high-altitude vegetation. The Hunstein Range-Bürgers Mountain-Schatteburg, Mt. Giluwe-Tari Gap-Doma Peaks CPD in PNG contains more than 2,500 vascular plant species and extensive stands of Agathis labillardieri and associated epiphytic flora. More than 3,000 vascular plant species are found in the Mt. Giluwe-Tari Gap-Doma Peaks CPD in PNG, including a unique Dacrydium swamp forest. The poorly known Kubor Ranges in PNG are a fragile ecosystem that probably contains many endemics on limestone and volcanic ash. The Bismarck Falls-Mt. Wilhelm-Mt. Otto-Schrader Range-Mt. Hellwig-Gahavisuka CPD has a wide variety of vegetation types and contains more than 5,000 vascular plant species. Important Araucaria cunninghamii, A. hunsteinii, and Castanopsis forests are found in the Mt. Michael-Okapa-Crater Mountain CPDs in PNG (Davis et al. 1995).

Current Status
The montane rain forests are generally undisturbed because of low population densities and traditional lifestyles. Some highland valleys are heavily populated, and this has resulted in local deforestation. A large and well-known hardrock mine is found in this ecoregion: the Freeport copper mine, located within the Lorentz Strict Nature Reserve in Irian Jaya. This is a large facility, and its location in a pristine area has caused concern about sedimentation and toxic runoff into adjacent stream and river systems. Petroleum extraction also occurs in Southern Highlands Province in PNG, but the environmental effects are minimal (Diamond and Bishop 1998). More than half of the Lorentz Nature Reserve is under petroleum concessions.

Almost 20 percent of the ecoregion is covered by eleven protected areas (table 3). The bulk of the protected area is in Irian Jaya, however (MacKinnon 1997). The largest protected area in the Central Ranges is the 21,500 km2 Gunung Lorentz Nature Reserve in the Snow Mountains of Irian Jaya, although only 7,350 km2 of the area is in this ecoregion (Stattersfield et al. 1998).

Table 3. WCMC (1997) Protected Areas That Overlap with the Ecoregion.

Protected Area Area (km2) IUCN Category
Pegunungan Weyland [AA0128], [AA1002] 1,830 PRO
Enarotali 3,540 IV
Gunung Lorentz [AA0121], 128, 129, 131] 7,350 I
Jayawijaya 7,710 IV
Jayawijaya extension [AA1002] 4,260 PRO
Mt. Capella [AA1002] 1,500 ?
Yakopi Nalenk Mts. [AA0115] 4,050 ?
Mt. Wilhelm [AA1002] 380 ?
Mt. Onuare [AA1002] 620 ?
Mt. Michael 1,160 ?
Mt. Bosavi [AA0122] 1,260 ?
Total 33,660  

Ecoregion numbers of protected areas that overlap with additional ecoregions are listed in brackets.

Types and Severity of Threats
Logging concessions have been granted for large areas of the ecoregion. The threat of increased access (and subsequent hunting and illegal logging) via new roads is a significant concern (Stattersfield et al. 1998). Mining poses threats in restricted locations.

Justification of Ecoregion Delineation
Using Whitmore's (1984) map of the vegetation of Malesia and MacKinnon's (1997) reconstruction of the original vegetation, we delineated the large areas of distinct habitat types as ecoregions. The montane evergreen moist forests along the Central Cordillera, including the Snow Mountains, Star Mountains, Central Highlands, and Eastern Highlands, were placed in the Central Range Montane Rain Forests [AA0105]. This ecoregion roughly corresponds to MacKinnon's subunits P3g, P3h, and P3i. The moist forests in the southeastern peninsula were distinguished as the Southeastern Papuan Rain Forests [AA0120]. This ecoregion consists mostly of montane forests but also includes some lowland forests along the coasts and is roughly equivalent to MacKinnon's (1997) biounit P3n. We used the 1,000-m contour from a DEM (USGS 1996) to define the montane-lowland transition. All along the Central Cordillera and in the Huon Peninsula, we separated the alpine habitat into a distinct (Central Range Sub-Alpine Grasslands [AA1002]) -ecoregion. Udvardy (1975) placed these ecoregions in the Papuan biogeographic province of the Oceanian Realm.

References for this ecoregion are currently consolidated in one document for the entire Indo-Pacific realm.
Indo-Pacific Reference List

Prepared by: John Morrison
Reviewed by:

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.