New Guinea Highlands - Ecology - Central Range Montane Rain Forests

Central Range Montane Rain Forests

The montane rain forests (from 1,000 to 3,000m) can be further categorised into three broad vegetation zones on the mountains, distinguished by elevation. The lower montane forests extend from 1,000 to 1,500 metres elevation. They are dominated by broadleaf evergreen trees, including Castanopsis acuminatissima, Lithocarpus spp., elaeocarps, and laurels. Coniferous Araucarias may form thick stands. The upper montane forests, which extend from 1,500 to 2,500 metres elevation, are dominated by moss-covered Nothofagus. Finally, the high mountain forest extends from 2,500 to 3,000 metres elevation. Conifers (Podocarpus, Dacrycarpus, Dacrydium, Papuacedrus, Araucaria, and Libocedrus) and broadleaf trees of the Myrtle family (Myrtaceae) form a thin canopy, with a prominent understory.

The montane forests are home to a rich wildlife, a great deal of which is unique to these mountains including a many of plants, reptiles and over 100 birds and animals. Of the 90 mammals found on the island, 44 are endemic, a very high proportion. The birds and animals include many Australasian species such as Tree-kangaroos, Bowerbirds, Australasian Robins, Honeyeaters, and Birds of Paradise. Four of the endemic mammals are critically endangered: the Bulmer's Fruit Bat, with only tiny communities remaining in the Papua New Guinea end of the island, and three rodents; a large Leptomys, the Eastern Shrew Mouse, and the Lesser Small-toothed Rat. There are 55 bird species endemic to the mountains from a total of 348 birds found here. There are a number of endemic butterflies, particularly on the Weyland Mountains and the Wahgi Valley.

Apart from in the cultivated valleys the montane forests are largely intact, although the logging industry is a constant threat as more and more access to the mountains is achieved by road building. 20% of this ecoregion is contained within protected areas, mostly in the Indonesian half of the island, including the largest protected area in South East Asia, the huge Lorentz National Park in the highlands, a section of which is montane forest ecosystem.