Central Range sub-alpine grasslands
The Central Range sub-alpine grasslands is a montane grasslands and shrublands ecoregion on the island of New Guinea. The ecoregion covers the highest-elevation portions of the New Guinea Highlands, which extend along the spine of the island. The high elevations support rare tropical sub-alpine and alpine habitats, including many endemic plants and animals.
Geography
The ecoregion includes isolated areas above 3000 metres elevation in the Central Range, or Central Cordillera, of New Guinea, and some outliers in the mountains of the Huon Peninsula. The Central Range extends east and west across New Guinea, with the western portion of the range in Indonesia and the eastern portion in Papua New Guinea. High-elevation areas in the highlands include the Snow Mountains in Indonesia's Papua Province, the Star Mountains on the Indonesia–Papua New Guinea border, the Central and Eastern Highlands of Papua New Guinea, and the Owen Stanley Range in Southeastern Papua.Below 3000 metres elevation, the sub-alpine grasslands transition to montane rain forests - the Central Range montane rain forests along most of the Central Range, the Southeastern Papuan rain forests in the southeast, and the Huon Peninsula montane rain forests on the Huon Peninsula.
Flora
Plant communities in the ecoregion include sub-alpine grasslands, shrublands, heathlands, and alpine grasslands.High mountain forests lie below the tree line, made up of conifers – species of Podocarpus, Dacrycarpus, Dacridium, Papuacedrus, Araucaria, and Libocedrus - and broadleaf trees in the myrtle family. The high mountain forests typically have a low, thin canopy and prominent understory. The tree line is approximately 3000 metres in elevation, which is the upper boundary of the Central Range montane rain forests ecoregion, but in places, forests extend up to 3900 metres.
Sub-alpine communities include shrubby heaths of Rhododendron, Vaccinium, Coprosma, Myrsine, and Saurauia at the forest edges, savannas of tree ferns above grasses, bogs, and grasslands. Low shrublands and Deschampsia tussock grasslands occur immediately below the alpine zone.
Alpine communities occur above 4000 metres and are composed of compact herbs, including species of Ranunculus, Potentilla, Gentiana, and Epilobium; grasses, including species of Poa and Deschampsia; ferns, mosses; and lichens. Rosette plants and cushion herbs, low ferns, mosses, and lichens become more abundant at increasing elevations and replace grasses above 4,300 metres elevation. Permanent ice, snow, and bare rock are found at the highest elevations.
Fauna
Only ten mammals are native to the ecoregion. These include three marsupials, a black-tailed dasyure, four murid rodents, glacier rat, and alpine woolly rat, two Microchiropteran bats, and the New Guinea singing dog ''. The western shrew mouse, glacier rat, and alpine wooly rat are endemic to the ecoregion.There are 84 native bird species in the ecoregion. Four species are strictly endemic – the Snow Mountain quail, Snow Mountain robin, Short-bearded honeyeater, and Long-bearded honeyeater.
Another 20 limited-range bird species inhabit the ecoregion and the adjacent lower-elevation montane forests. These limited-range species include the painted tiger parrot, Archbold's owlet-nightjar, Alpine pipit, Papuan thornbill, greater ground robin, Alpine robin, blue-capped ifrita, black sittella, Lorentz's whistler, orange-cheeked honeyeater, Huon honeyeater, spangled honeyeater, sooty honeyeater, Belford's honeyeater, rufous-backed honeyeater, black-backed honeyeater, mountain firetail, red satinbird, MacGregor's bird of paradise, brown sicklebill, Princess Stephanie's astrapia, splendid astrapia, ribbon-tailed astrapia, and Huon astrapia.