Lake Ira Lalaro (also Iralalaro, Ira-Lalaro, Surubec, Suro Bec) is a

freshwater lake A lake is an area filled with water, localized in a basin, surrounded by land, and distinct from any river or other outlet that serves to feed or drain the lake. Lakes lie on land and are not part of the ocean, although, like the much larger ...

in Mehara, Subdistrict

Tutuala Tutuala is a village and suco in the subdistrict of Tutuala (Lautém District, East Timor). It is situated at the extreme eastern end of Timor. Its population at the 2004 census was 3,707. The subdistrict of Tutuala comprises two sucos, inclu ...

Lautém District Lautém (Tetum: Lautein) is a toponym for a place eastmost in East Timor. It may refer to, from small to large: * Lautém (city) * Lautém Administrative Post * Lautém Municipality Lautém ( pt, Município Lautém, ) is one of the municip ...

East Timor East Timor (), also known as Timor-Leste (), officially the Democratic Republic of Timor-Leste, is an island country in Southeast Asia. It comprises the eastern half of the island of Timor, the exclave of Oecusse on the island's north-weste ...

. It is the largest of the island of

Timor Timor is an island at the southern end of Maritime Southeast Asia, in the north of the Timor Sea. The island is East Timor–Indonesia border, divided between the sovereign states of East Timor on the eastern part and Indonesia on the western p ...

, and thus too of the country. The lake is part of the Mount Paitchau

Important Bird Area An Important Bird and Biodiversity Area (IBA) is an area identified using an internationally agreed set of criteria as being globally important for the conservation of bird populations. IBA was developed and sites are identified by BirdLife Int ...

. The lake waters and that of Irasiquero River are a closed aquatic system; they lie within a huge

polje A polje, also karst polje or karst field, is a large flat plain found in karstic geological regions of the world, with areas usually . The name derives from the Slavic languages and literally means 'field', whereas in English ''polje'' specific ...

. It covers between while the

authigenic Authigenesis is the process whereby a mineral or sedimentary rock deposit is generated where it is found or observed. Such deposits are described as authigenic. Authigenic sedimentary minerals form during sedimentation by precipitation or recrys ...

catchment basin covers .

Geography and geology

Ira Lalaro is in the far east of Timor island, and is part of the

Nino Konis Santana National Park The Nino Konis Santana National Park is East Timor's first national park. The park, established on 15 August 2007, covers . It links important bird areas such as Lore, Mount Paitchau, Lake Ira Lalaro, and Jaco Island. The park also includes o ...

(, which was established in August 2007 by East Timor.) The lake is located in a basin bounded by the Paitchau Mountains, within the Lospalos plateau. The region has

karst Karst is a topography formed from the dissolution of soluble rocks such as limestone, dolomite, and gypsum. It is characterized by underground drainage systems with sinkholes and caves. It has also been documented for more weathering-resistant ro ...

ic formations of

limestone Limestone ( calcium carbonate ) is a type of carbonate sedimentary rock which is the main source of the material lime. It is composed mostly of the minerals calcite and aragonite, which are different crystal forms of . Limestone forms whe ...

, with dolines, blind

valley A valley is an elongated low area often running between Hill, hills or Mountain, mountains, which will typically contain a river or stream running from one end to the other. Most valleys are formed by erosion of the land surface by rivers ...

cave A cave or cavern is a natural void in the ground, specifically a space large enough for a human to enter. Caves often form by the weathering of rock and often extend deep underground. The word ''cave'' can refer to smaller openings such as sea ...

s and

spring Spring(s) may refer to: Common uses * Spring (season), a season of the year * Spring (device), a mechanical device that stores energy * Spring (hydrology), a natural source of water * Spring (mathematics), a geometric surface in the shape of a ...

s. Ira Lalaro has an average water spread area of , which varies from . It is in a high plateau depression at an elevation of "formed by a huge polje karst formation". The lake flows to the east and as the lake water recedes during the dry season the land exposed becomes a pasture or scrubby grassland. The lake basin is surrounded by tropical dry forest which is of biodiversity value. The Irasiquero River, which originates from Lake Ira Lalaru, disappears in the main sink hole, the Mainina, about downstream of the lake outlet, and does not re-appear; tracer studies indicate that the underground route of water flow leads to the coast. There are human settlements in the area.

Biodiversity

The biodiversity of the lake's aquatic system, including the Irasiquero River, is that of a wetland ecosystem. The forest area is largely undisturbed. In the absence of continuous surface water flow, the invertebrates found in the lake and in the river consist of

macroinvertebrate Invertebrates are a paraphyletic group of animals that neither possess nor develop a vertebral column (commonly known as a ''backbone'' or ''spine''), derived from the notochord. This is a grouping including all animals apart from the chordate s ...

belonging to 57 families but sans decapod

crustaceans Crustaceans (Crustacea, ) form a large, diverse arthropod taxon which includes such animals as decapods, seed shrimp, branchiopods, fish lice, krill, remipedes, isopods, barnacles, copepods, amphipods and mantis shrimp. The crustacean group ...

. The Island pitviper (''Trimeresurus insularis'') and wood scorpions (''Lychas mucronatus'') are reported in the flood plains of the lake. Estuarine crocodiles (''Crocodylus porosus'') (about 300–350) are also found in the lake. It is not hunted by local people as it is their

totem A totem (from oj, ᑑᑌᒼ, italics=no or ''doodem'') is a spirit being, sacred object, or symbol that serves as an emblem of a group of people, such as a family, clan, lineage, or tribe, such as in the Anishinaabe clan system. While ''the wo ...

animal connected to their creation story and known as "lafaek" in the

Tetum language , nativename=Tetun , states= Indonesia East Timor , speakers=, mostly in Indonesia , date=2010–2011 , ref=e18 , speakers2=50,000 L2-speakers in Indonesia and East Timor , familycolor=Austronesian , fam2=Malayo-Polynesian , fam3= Central–East ...

. Boats are banned on the lake, based on a traditional belief that the fish in the lake will die when boats enter the water. Villagers were forced to stand in the water to fish, and fatal crocodile attacks were common. Recently fishermen appear to be using rafts to avoid crocodile attacks. The Timor snake-necked turtle (''Chelodina mccordi timorensis'') is also endemic to the lake and the river. The local dialect name is ‘‘beo’’, the Tetum name is "lenok kakorok ular" and an alternative English name is Timor long-necked turtle. ''Chelodina mccordi'' is considered to be one of the 25 most endangered turtles in the world and is protected under

CITES CITES (shorter name for the Convention on International Trade in Endangered Species of Wild Fauna and Flora, also known as the Washington Convention) is a multilateral treaty to protect endangered plants and animals from the threats of interna ...

Appendix II. There are 21 fish species in the lake including an endemic species of hardyhead (''Craterocephalus laisapi''), found in the middle section of the Irasiquero River. In a number of field surveys of East Timorese waterbirds and coastal seabirds of carried out in the 2000s, the lake's wetland was identified as one of three wetlands of high national significance in that country, and as being one of the most notable wetlands in

Wallacea Wallacea is a biogeographical designation for a group of mainly Indonesian islands separated by deep-water straits from the Asian and Australian continental shelves. Wallacea includes Sulawesi, the largest island in the group, as well as Lo ...

. The lake area has both migratory and resident water birds. It is part of the Mount Paitchau and Lake Ira Lalaro

(IBA). One of globally threatened bird species reported is the

yellow-crested cockatoo The yellow-crested cockatoo (''Cacatua sulphurea'') also known as the lesser sulphur-crested cockatoo, is a medium-sized (about 34-cm-long) cockatoo with white plumage, bluish-white bare orbital skin, grey feet, a black bill, and a retractile y ...

(''Cacatua sulphur''), which is considered critically endangered. Other species reported are:

Australian pelican The Australian pelican (''Pelecanus conspicillatus'') is a large waterbird in the family Pelecanidae, widespread on the inland and coastal waters of Australia and New Guinea, also in Fiji, parts of Indonesia and as a vagrant in New Zealand. It ...

(''Pelecanus conspicillatus''),

wandering whistling duck The wandering whistling duck (''Dendrocygna arcuata'') is a species of whistling duck. They inhabit tropical and subtropical Australia, the Philippines, Borneo, Indonesia, Papua New Guinea and the Pacific Islands. Taxonomy There are three subspe ...

(''Dendrocygna arcuata''),

common coot The Eurasian coot (''Fulica atra''), also known as the common coot, or Australian coot, is a member of the rail and crake bird family, the Rallidae. It is found in Europe, Asia, Australia, New Zealand and parts of North Africa. It has a slaty-bla ...

(''Fulica atra''),

Swinhoe's snipe Swinhoe's snipe, (''Gallinago megala''), also known as forest snipe or Chinese snipe, is a medium-sized (length 27–29 cm, wingspan 38–44 cm, weight 120 gm), long-billed, migratory wader. The common name commemorates the British na ...

(''Gallinago megala''), Australasian grebe (''Tachybaptus novaehollandiae''), Timor green pigeon (''Treron psittaceus''),

cinnamon-banded kingfisher The cinnamon-banded kingfisher (''Todiramphus australasia'') is a species of bird in the family Alcedinidae. It is found in Indonesia and East Timor. It is endemic to the Lesser Sundas. Its natural habitat is subtropical or tropical dry forests. I ...

(''Todiramphus australasia''), spot-breasted white-eye (''Heleia muelleri''), and

black-banded flycatcher The black-banded flycatcher (''Ficedula timorensis''), also known as the Timor flycatcher, is a species of bird in the family Muscicapidae. In the past the species was considered to be related to the Australasian robins but this was as the resul ...

(''Ficedula timorensis''). There are 16 species of

bat Bats are mammals of the order Chiroptera.''cheir'', "hand" and πτερόν''pteron'', "wing". With their forelimbs adapted as wings, they are the only mammals capable of true and sustained flight. Bats are more agile in flight than most bi ...

s (cave roosters), including Geoffroy's rousette fruit bat (''Rousettus amplexicaudatus''),

Canut's horseshoe bat Canut's horseshoe bat (''Rhinolophus canuti'') is a species of bat in the family Rhinolophidae. It is endemic to Indonesia. Taxonomy and etymology It was described as a new species in 1909 by Oldfield Thomas and Robert Charles Wroughton. They ...

(''Rhinolophus canuti''), and Sumba round leaf bat (''Hipposideros sumbae'').

References

External links

{{commons category, Lake Ira Lalaro Lakes of Asia Bodies of water of East Timor Important Bird Areas of East Timor