The Yapen rain forests is a
tropical moist forest ecoregion
An ecoregion (ecological region) is an ecological and geographic area that exists on multiple different levels, defined by type, quality, and quantity of environmental resources. Ecoregions cover relatively large areas of land or water, and c ...
in
Indonesia
Indonesia, officially the Republic of Indonesia, is a country in Southeast Asia and Oceania, between the Indian Ocean, Indian and Pacific Ocean, Pacific oceans. Comprising over List of islands of Indonesia, 17,000 islands, including Sumatra, ...
. The ecoregion covers the island of
Yapen
Yapen (also Japen, Jobi) is an island of Papua (province), Papua, Indonesia. The Yapen Strait separates Yapen and the Biak Islands to the north. It is in Cenderawasih Bay off the north-western coast of the island of New Guinea. To the west is ...
and smaller neighboring islands which lie north of
New Guinea
New Guinea (; Hiri Motu: ''Niu Gini''; , fossilized , also known as Papua or historically ) is the List of islands by area, world's second-largest island, with an area of . Located in Melanesia in the southwestern Pacific Ocean, the island is ...
.
Geography
The ecoregion covers the island of Yapen, and the smaller islands of
Mios Num to the northwest and Kurudu to the east.
[
Yapen covers an area of 2,230 km2. The island is long and narrow, extending 166 km east and west and only 26 km north to south at the island's widest point. Hills and mountains run the length of the island. The highest peak is 1,430 m.][Jared Diamond, K. David Bishop "Origins of the upland avifauna of Yapen Island, New Guinea region," Bulletin of the British Ornithologists’ Club, 140(4), 423-448, (9 December 2020)]
The surface geology is limestone and plutonic rocks, including outcrops of ultramafic rock.[
The islands were connected to New Guinea during the ice ages when the sea level was lower, and shares many plants and animals with the adjacent mainland.][
]
Climate
The ecoregion has a tropical rain forest climate.[
]
Flora
The original vegetation was tropical wet evergreen forest. Forests consisted of three main types, alluvial forests in flatlands and river valleys, and hill forest on the hillsides, and montane forests at higher elevations.[
Dominant trees on the coastal strand are '']Terminalia catappa
''Terminalia catappa'' is a large Tropics, tropical tree in the leadwood tree family, Combretaceae, native to Asia, Australia, the Pacific, Madagascar and Seychelles. Common names in English include country almond, Indian almond, Malabar almond, ...
, Barringtonia asiatica, Calophyllum inophyllum, Artocarpus'' sp., and '' Casuarina'' sp. Swamp forests of Nipa palm (''Nypa fruticans'') are common behind the shore. '' Palaquium amboinense, Octomeles sumatrana, Intsia bijuga, Ficus benjamina'', and species of '' Eugenia'' and '' Artocarpus'' cover lowland slopes. ''Palaquium amboinense, Octomeles sumatrana, Calophyllum'' sp., ''Terminalia'' sp., ''Manilkara'' sp., '' Pometia acuminata'', and '' Pometia pinnata'' predominate in lowland forests further inland, with '' Anisoptera thurifera polyandra'' as an emergent tree in scattered locations.[
Characteristic trees of the highlands include ''Pometia acuminata, Palaquium amboinense'', and species of '' Cryptocarya, Tristania,'' and ''Calophyllum''.][ The conifer '' Araucaria cunninghamii'' is an emergent tree found in scattered mountain locations above 500 meters elevation.][
Ultramafic rocks contain concentrations of metals which are toxic to many plants, and the ultramafic outcrops host unique plant communities adapted to ultramafic soils.][
]
Fauna
The ecoregion is home to 37 mammal species.[Wikramanayake, Eric; Eric Dinerstein; Colby J. Loucks; et al. (2002). ''Terrestrial Ecoregions of the Indo-Pacific: a Conservation Assessment.'' Washington, DC: Island Press.] Two limited-range species are shared with the Biak–Numfoor rain forests ecoregion, which covers the islands north of Yapen: the Japen rat (''Rattus jobiensis'') is found on Yapen and the islands of Biak and Supiori,[ and the Geelvink Bay flying fox (''Pteropus pohlei''), a fruit bat, is found on Yapen and the islands of Numfor and Rani.
147 bird species live in the ecoregion.][ There are no strictly endemic bird species. About 120 species live in the lowlands, and 26 species live in the uplands.][ The montane forests are home to the Green-backed robin (''Pachycephalopsis hattamensis''), which also lives in New Guinea's Central and Vogelkop highlands.]["Yapen". Birdlife International. Accessed 10 July 2021]
/ref> The island's largest bird is the Northern cassowary (''Casuarius unappendiculatus'').
Protected areas
48.31% of the ecoregion is in protected areas. Yapen Tengah Nature Reserve is the largest protected area in the ecoregion, covering 590.0 km2 in the center of the island.["Yapen Tengah". ''Protected Planet''. Accessed 11 July 2021]
/ref>
External links
*
Yapen endemic bird area (Birdlife International)
Yapen rain forests (DOPA Explorer)
References
{{reflist
Australasian ecoregions
Ecoregions of Indonesia
Tropical and subtropical moist broadleaf forests
Yapen Islands