The Palawan rain forests

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 ...

(WWF ID:IM0143) covers the

Palawan Palawan (, ), officially the Province of Palawan (; ), is an archipelagic province of the Philippines that is located in the region of Mimaropa. It is the largest province in the country in terms of total area of . The capital and largest c ...

Island Archipelago, centered on

Palawan Island Palawan () is the largest island of the province of Palawan in the Philippines and fifth-largest by area and tenth-most populous island of the country, with a total population of 994,101 as of 2020 census. The northwest coast of the island is a ...

, the sixth largest island in the

Philippines The Philippines, officially the Republic of the Philippines, is an Archipelagic state, archipelagic country in Southeast Asia. Located in the western Pacific Ocean, it consists of List of islands of the Philippines, 7,641 islands, with a tot ...

. The islands act as an ecological bridge between

Borneo Borneo () is the List of islands by area, third-largest island in the world, with an area of , and population of 23,053,723 (2020 national censuses). Situated at the geographic centre of Maritime Southeast Asia, it is one of the Greater Sunda ...

and the main islands of the Philippines, even though there were channels between the islands through the last ice age when sea levels were low. Biodiversity is high in the islands, with many endemic species, and with many genera shared with Borneo to the south. Pressure from logging is a concern for the forests of this region.

Location and description

In addition to the main island of

, the ecoregion includes

Balabac Island Balabac Island is the southernmost island of Palawan province, and therefore the westernmost undisputed island in the Philippines, some north of Sabah, Malaysia, across the Balabac Strait. Administratively, the island forms the main part of th ...

to the south, Ursula Island, and the

Calamian Islands The Calamian Islands or the Calamianes is a group of islands in the province of Palawan, Philippines. It includes: * Busuanga Island * Coron Island * Culion Island * Calauit Island * Malcapuya Island * Banana Island * Pass Island * Calumbuyan ...

to the north. Palawan Island is 260 km long and averages only 25–30 km wide. A mountain range runs up the middle of the island, with almost half of the slopes averaging over 30 degrees. The highest point is at

Mount Mantalingajan Mount Mantalingajan (or Mantalingahan or Mantaling) is the highest mountain in the island province of Palawan in the Philippines, with an elevation of above sea level, its ranked List of islands by highest point, 68th-highest peak of an island ...

. The islands are relatively young, having been lifted up from the sea only 5-10 million years ago.

Climate

The climate of the ecoregion is '' Tropical savanna climate - dry winter'' (

Köppen climate classification The Köppen climate classification divides Earth climates into five main climate groups, with each group being divided based on patterns of seasonal precipitation and temperature. The five main groups are ''A'' (tropical), ''B'' (arid), ''C'' (te ...

(Aw)). This climate is characterized by relatively even temperatures throughout the year, and a pronounced dry season. The driest month has less than 60 mm of precipitation, and is drier than the average month. In the Palawans, the wet season lasts from June to October. The dry season for much of the island is November to May, but only a few months long in the north.

Flora

About two thirds of the islands is covered in closed broadleaf evergreen forest, 10% in other closed forest, 15% in open forest or herbaceous cover and only about 5% in human settlement or agriculture. Much of this forest below the highlands has been cut previously, and pressure from logging and conversion of land to agriculture has reduced the quality of much of the forest. The forests nearest the coast are beech forests, transitioning to lowland

rain forest Rainforests are forests characterized by a closed and continuous tree Canopy (biology), canopy, moisture-dependent vegetation, the presence of epiphytes and lianas and the absence of wildfire. Rainforests can be generally classified as tropi ...

dominated by trees of the

Dipterocarpaceae Dipterocarpaceae is a family (biology), family of flowering plants with 22 genera and about 695 known species of mainly lowland tropical forest trees. Their distribution is pantropical, from northern South America to Africa, the Seychelles, India ...

family, Agalai, various species of ''

Ficus ''Ficus'' ( or ) is a genus of about 850 species of woody trees, shrubs, vines, epiphytes and hemiepiphytes in the family (biology), family Moraceae. Collectively known as fig trees or figs, they are native throughout the tropics with a few spe ...

'', Water gum ''( Tristania)'', Broad leaved ballart ''(

Exocarpos latifolius ''Exocarpos latifolius'' is a species of parasitic tree, in the plant family Santalaceae. They have the common names broad leaved ballart, scrub sandal-wood, scrub cherry, oringorin, broad leaved cherry or native cherry. The species is found in ...

)'', and '' Swintonia foxworthyi''. Montane rainforest is found at higher elevations (800 to 1,200 meters), and semi-deciduous forest is found in the rain shadow on the east side of the main island. The southern part of the main island has different forest types that depend on the soil. Large areas are limestone forest, featuring cathedral cactus ''( Euphorbia lacei)'', ''

Aglaia argentea ''Aglaia argentea'' is a species of plants in the family Meliaceae. It is a tree found in Australia, Brunei, India, Indonesia, Malaysia, Myanmar, Papua New Guinea, the Philippines, the Solomon Islands, and Thailand. Description ''Aglaia arge ...

'', and species of '' Antidesma'', '' Drypetes'', and ''

Gomphandra ''Gomphandra'' is a genus of plant in family Stemonuraceae. They are dioecious trees or shrubs.Barlow, B.A. (1984) in George, A.S. (edFlora of Australia. Volume 22. Rhizophorales to Celastrales Commonwealth of Australia, Canberra. The genus incl ...

''. There are

ultramafic Ultramafic rocks (also referred to as ultrabasic rocks, although the terms are not wholly equivalent) are igneous and meta-igneous rocks with a very low silica content (less than 45%), generally >18% MgO, high FeO, low potassium, and are usua ...

forests around Victoria Peak that support plants that may be associated with soils having heavy metals. Parts of the southern forest are dominated by ''

Casuarina ''Casuarina'', also known as she-oak, Australian pine and native pine, is a genus of flowering plants in the family Casuarinaceae, and is native to Australia, the Indian subcontinent, Southeast Asia, islands of the western Pacific Ocean, and e ...

''.

Fauna

There are high levels of endemic species of mammals on the islands, but many of the genera are shared with Borneo, indicating that the Palawans were once part of

Sundaland Sundaland (also called Sundaica or the Sundaic region) is a biogeographical region of Southeast Asia corresponding to a larger landmass that was exposed throughout the last 2.6 million years during periods when sea levels were lower. It inc ...

(the combined islands to the west), but have been separated for enough time to develop their own faunal communities.

Protected areas

Over 80% of the ecoregion is protected in some form. These protected areas include: *

Puerto Princesa Subterranean River National Park The Puerto Princesa Subterranean River National Park is a protected area in the Philippines. The park is located in the Saint Paul Mountain Range on the western coast of the island of Palawan, about north of the city of Puerto Princesa, and c ...

References

{{reflist Indomalayan ecoregions Ecoregions of the Philippines Tropical and subtropical moist broadleaf forests Palawan