The Christmas and Cocos Islands tropical forests

ecoregion An ecoregion (ecological region) or ecozone (ecological zone) is an ecologically and geographically defined area that is smaller than a bioregion, which in turn is smaller than a biogeographic realm. Ecoregions cover relatively large areas of l ...

(WWF ID: IM0110) covers forested areas of

Christmas Island Christmas Island, officially the Territory of Christmas Island, is an Australian external territory comprising the island of the same name. It is located in the Indian Ocean, around south of Java and Sumatra and around north-west of the ...

and

North Keeling Island North Keeling is a small, uninhabited coral atoll, approximately in area, about north of Horsburgh Island. It is the northernmost atoll and island of the Australian territory of the Cocos (Keeling) Islands. It consists of just one C-shaped i ...

, two small seamount islands south of the Indonesian island of

Java Java (; id, Jawa, ; jv, ꦗꦮ; su, ) is one of the Greater Sunda Islands in Indonesia. It is bordered by the Indian Ocean to the south and the Java Sea to the north. With a population of 151.6 million people, Java is the world's List ...

. The forests of these two islands share tree species of the Indo-Pacific and Melanesian types on nearby islands, the forests of Christmas Island and North Keeling Island are unique in how they reflect the effects of large populations of terrestrial red crabs (''

Gecarcoidea natalis The Christmas Island red crab (''Gecarcoidea natalis'') is a species of land crab that is endemic to Christmas Island and Cocos (Keeling) Islands in the Indian Ocean. Although restricted to a relatively small area, an estimated 43.7 million adu ...

''). Because of the remoteness of the islands, there are many endemic species.

Location and description

Christmas Island

Christmas Island, 350 km southwest of the island of

, is mostly forested. Of its 135 km2 total area, 85 km2 is protected by the

Christmas Island National Park Christmas Island National Park is a national park occupying most of Christmas Island, an Australian territory in the Indian Ocean southwest of Indonesia. The park is home to many species of animal and plant life, including the eponymous Christma ...

. The island is a limestone cover of an ancient submerged volcano, with eroded terraces and an interior plateau.

Cocos (Keeling) Islands

Of the

Cocos (Keeling) Islands ) , anthem = "''Advance Australia Fair''" , song_type = , song = , image_map = Australia on the globe (Cocos (Keeling) Islands special) (Southeast Asia centered).svg , map_alt = Location of the Cocos (Keeling) Islands , map_caption = ...

, only

has significant forest, the other islands having mostly been converted to agricultural uses. North Keeling Island is 900 km southwest of Christmas Island. The Cocos Islands are also built on submerged seamounts, but the surface is limited to a low-lying coral atoll.

Climate

The climate of the ecoregion is ''

Tropical monsoon climate An area of tropical monsoon climate (occasionally known as a sub-equatorial, tropical wet climate or a tropical monsoon and trade-wind littoral climate) is a tropical climate sub-type that corresponds to the Köppen climate classification category ...

'' (

Köppen climate classification The Köppen climate classification is one of the most widely used climate classification systems. It was first published by German-Russian climatologist Wladimir Köppen (1846–1940) in 1884, with several later modifications by Köppen, notabl ...

(Am)). This climate is characterized by relatively even temperatures throughout the year (all months being greater than average temperature), and a pronounced dry season. This climate is mid-way between a tropical rainforest and a tropical savannah. On Christmas Island, the temperatures average from and an average humidity of 80-90% (Gray 1981). Precipitation averages 2,000 mm/year. The wet monsoon season is from December to April.

Flora and fauna

The forests of the ecoregion have a dense canopy at , little undergrowth, and a wide range of

epiphytes An epiphyte is an organism that grows on the surface of a plant and derives its moisture and nutrients from the air, rain, water (in marine environments) or from debris accumulating around it. The plants on which epiphytes grow are called phoroph ...

. Some trees reach . The characteristic tree species are ''

Planchonella nitida ''Planchonella duclitan'' is a species of plant in the family Sapotaceae. A tree that may attain a height of 40 meters, presenting glossy leaves and orange fruit. It is common on Christmas Island, dominating up to 20% of the upper leaf canopy, as ...

'', ''

Syzygium nervosum ''Syzygium nervosum'' is a species of tree native to tropical Asia and Australia, extending as far north as Guangdong and Guangxi in China and as far south as the Northern Territory of Australia. It was previously known as ''Cleistocalyx opercul ...

'', '' Tristiropsis acutangula'', ''

Inocarpus fagifer ''Inocarpus fagifer'', commonly known as the Tahitian chestnut or Polynesian chestnut, is a species of flowering plant in the subfamily Faboideae of the legume family, Fabaceae. The tree has a wide range in the tropics of the south-west Pacific a ...

'', and ''

Hernandia ovigera ''Hernandia'' is a genus of flowering plants in the family Hernandiaceae. It was named after the Spanish botanist Francisco Hernández de Toledo. Species , ''Plants of the World Online'' accepted the following species: * ''Hernandia albiflora'' ...

''. Undergrowth that exists is typically the vulnerable Lister's palm (''

Arenga listeri ''Arenga listeri'', the Lister's palm, is a species of flowering plant in the family Arecaceae. It is named after naturalist Joseph Jackson Lister. It is endemic to Christmas Island and is threatened by habitat loss. The palm is featured on a ...

'') and '' Pandanus elatus ''. Over 100 million red crabs (''

'') are estimated to live in the woods; they keep most of the forest floor clear of fallen leaves and other litter. Christmas Island is also home to the vulnerable Christmas Island hawk-owl ('' Ninox natalis'').

Protected areas

About 9% of the ecoregion is part of an officially protected area, including: *

* Pulu Keeling National Park

References

{{reflist Indomalayan ecoregions Ecoregions of Australia Tropical and subtropical moist broadleaf forests