Location and General Description
This ecoregion represents the upper montane habitat on Mt. Kinabalu and the Crocker Range and the surrounding upland areas in the Malaysian state of Sabah (Borneo). Thirty-five million years ago marine sediments were transformed to rock in the area where Mt. Kinabalu now stands. Approximately 25 million years ago these layers of shale and sandstone were uplifted to form a mountain range. The eroded remains of this range are now known as the Crocker Range. Approximately 15 million years ago a large mass of magma intruded between the folds of the Crocker Range and solidified into adamellite (a type of granite). This intrusion was uplifted rapidly, at a rate of an inch every five years. The exposed granite body, which is still growing, is Mt. Kinabalu. At 13,455 feet it is the highest mountain between the Himalayas and New Guinea (Myers 1978; Jacobson 1978). Based on the Köppen climate zone system, this ecoregion falls in the tropical wet climate zone (National Geographic Society 1999).
Kinabalu is the meeting place for plant species from the Himalayas, China, Australia, New Zealand, and the Indo-Malayan realm (Corner 1978). The vegetation of Kinabalu can be divided into zones based on altitude, but many factors may alter their distribution locally to either higher or lower elevations. Above 1,000 m a montane zone exists until about 2,600 m. This zone includes a mixing of lowland and montane families, giving this elevation zone a great diversity of life. The common lowland families, such as Dipterocarpaceae, Euphorbiaceae, Leuminosae, Myristicaceae, and Sapotaceae, begin to diminish, and they begin to be replaced by a great diversity of species from plant families such as Ericaceae, Myrtaceae, Fagaceae, Lauraceae, Magnoliaceae, and the majority of Bornean gymnosperms, including Podocarpus, Agathis, and Phyllocladus. The dipterocarp Shorea monticola occurs in this elevation belt but not in the lowlands. This elevation zone also supports a number of endemic species from Rhododendron, Lithocarpus, Magnolia, and Rhamnus. A large variety of pitcher plants, many endemic Mt. Kinabalu, occur in this zone (Cockburn 1978). The endemic species include Nepenthes edwardsiana, N. rajah, N. villosa, and N. burbidgeae. The most common species found in these forests is the spectacular Nepenthes lowii. Fig trees are also common in these forests. Borneo has 135 species of wild figs, with more than 78 species occurring on Kinabalu, including 13 endemic species (Corner 1952). Kinabalu may have one of the richest fig floras in the world (Corner 1978). This floristically rich area also supports Rafflesia tengku-adlinii (which occurs only on Trus Madi and in the Maliau Basin) (WWF and IUCN 1995).
Between 2,600 and 3,200 m is a band of ultrabasic rocks that give rise to a different type of vegetation. This vegetation ranges from the 10-m high Dacrydium gibbsiae to dwarf shrubs and includes moss, lichen, liverwort, and ferns. Above 3,200 m the soil cover soon disappears, giving way to granite. In areas where soil can support shrubs, species such as Leptospermum recurvum, Coprosma hookeri, and Rhododendron buxifolium dominate. On thinner soil, herbs such as Diplocosia kinabaluensis, Machaerarina falcata, and Ranunculus lowii are common (Cockburn 1978).
This ecoregion contains more than 750 orchid species in more than sixty genera. This number accounts for more than one-fourth of all orchid species found in Malesia (Lamb and Chan 1978). Perhaps the most famous orchid species found on Kinabalu are the several species of slipper orchid, Paphiopedilum. However, because of intensive collecting, they are rarely seen. The montane region of Kinabalu presents a variety of microhabitats that have produced many orchid species common to Eria, Bulbophyllum, Dendrobium, Liparis, Dendrochilum, Pholidota, and Coelogyne (Lamb and Chan 1978).
Most of the 114 mammal species found in this ecoregion live in the forest canopy. Only one-third of the mammal species are terrestrial. Common terrestrial species include three deer species, the Malaysian weasel (Mustela nudipes), small-clawed otter (Aonyx cinerea), and leopard cat (Felis bengalensis). The majority of the species live in the canopy of the forests. These species include many of the twenty-eight of the thirty-four squirrels known from Borneo, numerous bat species, tree shrews, slow loris, tarsier (Tarsius bancanus), grey leaf monkey (Presbytis aygula), red leaf monkey (P. rubicunda), orangutan (P. pygmaeus), Borneo gibbon (Hylobates moloch), linsang (Prionodon linsang), and binturong (Arctictis binturong). There are twelve near-endemic and four endemic mammal species, which include the Bornean black shrew (Suncus ater) and Bornean ferret-badger (Melogale everetti) (table 1).
Table 1. Endemic and Near-Endemic Mammal Species.
Crocidurinae Suncus ater*
Sorcidae Crocidura baluensis
Tupaiidae Tupaia montana
Cercopithecidae Presbytis comata
Mustelidae Melogale everetti*
Sciuridae Callosciurus baluensis
Sciuridae Callosciurus orestes
Sciuridae Glyphotes simus
Sciuridae Sundasciurus brookei
Sciuridae Petaurillus hosei
Sciuridae Aeromys thomasi
Muridae Rattus baluensis*
Muridae Chiropodomys muroides*
Muridae Maxomys alticola
Muridae Maxomys ochraceiventer
Muridae Maxomys baeodon
An asterisk signifies that the species' range is limited to this ecoregion.
This ecoregion also supports more than 180 bird species. The bird fauna includes twenty-four near-endemic species and one endemic species (table 2). The ecoregion overlaps with a portion of the Bornean Mountains EBA (157) (Stattersfield et al. 1998).
Table 2. Endemic and Near-Endemic Bird Species.
Family Common Name Species
Accipitridae Mountain serpent-eagle Spilornis kinabaluensis
Phasianidae Red-breasted partridge Arborophila hyperythra
Phasianidae Crimson-headed partridge Haematortyx sanguiniceps
Podargidae Dulit frogmouth Batrachostomus harterti
Trogonidae Whitehead's trogon Harpactes whiteheadi
Capitonidae Mountain barbet Megalaima monticola
Capitonidae Golden-naped barbet Megalaima pulcherrima
Capitonidae Bornean barbet Megalaima eximia
Eurylaimidae Whitehead's broadbill Calyptomena whiteheadi
Pachycephalidae Bornean whistler Pachycephala hypoxantha
Turdidae Everett's thrush Zoothera everetti
Turdidae Fruit-hunter Chlamydochaera jefferyi
Muscicapidae Eyebrowed jungle-flycatcher Rhinomyias gularis
Zosteropidae Black-capped white-eye Zosterops atricapillus
Zosteropidae Pygmy white-eye Oculocincta squamifrons
Zosteropidae Mountain black-eye Chlorocharis emiliae
Sylviidae Bornean stubtail Urosphena whiteheadi
Sylviidae Friendly bush-warbler Bradypterus accentor
Timaliidae Sunda laughingthrush Garrulax palliatus
Timaliidae Bare-headed laughingthrush Garrulax calvus
Timaliidae Mountain wren-babbler Napothera crassa
Timaliidae Chestnut-crested yuhina Yuhina everetti
Dicaeidae Black-sided flowerpecker Dicaeum monticolum
Nectariniidae Bornean spiderhunter Arachnothera everetti*
Nectariniidae Whitehead's spiderhunter Arachnothera juliae
An asterisk signifies that the species' range is limited to this ecoregion.
About one-third of this sensitive, high-altitude ecoregion has been cleared or degraded, mostly by agriculture or other practices associated with forest clearance. There are two protected areas in the ecoregion that cover a total of 1,440 km2 (33 percent) (table 3). Kinabalu Park was gazetted in 1964, and the Crocker Range National Park was established in this ecoregion in 1984.
Table 3. WCMC (1997) Protected Areas That Overlap with the Ecoregion.
Protected Area Area (km2) IUCN Category
Kinabalu [IM0123] 590 II
Crocker Range [IM0123] 850 II
Ecoregion numbers of protected areas that overlap with additional ecoregions are listed in brackets.
Types and Severity of Threats
The unique flora found on the slopes of Mt. Kinabalu is protected to some extent by the steepness of the terrain and poor soil conditions, which discourage logging and farming. Nevertheless, some of the surrounding slopes outside the park boundary are being cleared for farming, mainly of vegetables. Road construction has facilitated tourist access to Kinabalu Park, which has led to the construction of more facilities. Some of these developments have been poorly planned and even detrimental, such as the degazettement of a large area of alluvial Pinosuk Plateau in 1984 for government development projects such as a golf course and the 1984 redesignation of Trus Madi from a watershed protection forest to that of a commercial forest reserve to allow logging to take place. Commercial logging may have encroached into the park, and a section of the park was excised in 1974 for the development of a copper mine. A number of species, especially the rare and endemic species in the ecoregion, are being overcollected for the commercial wildlife and plant trade (WWF and IUCN 1995). These problems are exacerbated by the absence of buffer zones around the park and insufficient staff to enforce regulations.
Justification of Ecoregion Delineation
The large island of Borneo was divided into nine ecoregions. MacKinnon and MacKinnon (1986) divided the island's lowland forests into six subunits with a central subunit representing the montane forests. MacKinnon (1997) revised the boundaries of these seven subunits but retained the same general configuration. These authors used the major rivers, the Kapuas and Barito, to represent zoogeographic barriers to a few species of mammals and based subunits largely on these barriers but also used climatic regimes for the drier eastern biounits (MacKinnon and MacKinnon 1986; MacKinnon 1997).
Because ecoregions are based on biomes, we first isolated the central montane ecoregion-the Borneo Montane Rain Forests [IM0103]-above the 1,000-m elevation contour using the DEM (USGS 1996). We then assigned the large patches of peat forests, heath forests, freshwater swamp forests, and mangroves, in the lowlands and along the periphery of the island, into their own ecoregions: the Borneo Peat Swamp Forests [IM0104], Sundaland Heath Forests [IM0161] (which also includes Belitung Island and the heath forests on Bangka Island), and Southern Borneo Freshwater Swamp Forests [IM0153], and Sunda Shelf Mangroves [IM1405], respectively. The alpine habitats of the Kinabalu Mountain Range were represented by the Kinabalu Montane Alpine Meadows [IM1001]. Udvardy (1975) combined all of Borneo into the Borneo biogeographic province.
References for this ecoregion are currently consolidated in one document for the entire Indo-Pacific realm.
Indo-Pacific Reference List
Prepared by: Colby Loucks