Lake Barombi Mbo or Barombi-ma-Mbu is a lake near

Kumba Kumba is a metropolitan city in the Meme department, Southwest Region, Western Cameroon, referred as "K-town" in local slang. Kumba is the most developed and largest city in the Meme Department and has attracted people from the local villag ...

in the Southwest Region of

Cameroon Cameroon (; french: Cameroun, ff, Kamerun), officially the Republic of Cameroon (french: République du Cameroun, links=no), is a country in west-central Africa. It is bordered by Nigeria to the west and north; Chad to the northeast; the C ...

. It is located in the Cameroon volcanic chain, and is the largest

volcanic lake A volcanogenic lake is a lake formed as a result of volcanic activity. They are generally a body of water inside an inactive volcanic crater (crater lakes) but can also be large volumes of molten lava within an active volcanic crater (lava lakes) ...

in this region. It is one of the oldest radiocarbon-dated lakes in Africa, with the youngest

lava flow Lava is molten or partially molten rock (magma) that has been expelled from the interior of a terrestrial planet (such as Earth) or a moon onto its surface. Lava may be erupted at a volcano or through a fracture in the crust, on land or und ...

in it being about one million years old. On old colonial maps the area was known as Elefanten Sea (Elephant Lake), but the

elephants Elephants are the largest existing land animals. Three living species are currently recognised: the African bush elephant, the African forest elephant, and the Asian elephant. They are the only surviving members of the family Elephantidae and ...

living in the area were

extirpated Local extinction, also known as extirpation, refers to a species (or other taxon) of plant or animal that ceases to exist in a chosen geographic area of study, though it still exists elsewhere. Local extinctions are contrasted with global extinct ...

due to ivory trading.

Biology

Until now, 15 species of fishes have been recorded from the lake.Freshwater Ecoregions of the World (2008).
Western Equatorial Crater Lakes.
'' Among others, this includes ''

Labeobarbus batesii ''Labeobarbus batesii'' is a species of cyprinid fish from Africa that occurs in Cameroon, Chad and Gabon Gabon (; ; snq, Ngabu), officially the Gabonese Republic (french: République gabonaise), is a country on the west coast of Central ...

'', a member of the '' Fundulopanchax mirabilis'' group, and the

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsew ...

catfish '' Clarias maclareni''. Perhaps most noteworthy are the 11 species of

cichlid Cichlids are fish from the family Cichlidae in the order Cichliformes. Cichlids were traditionally classed in a suborder, the Labroidei, along with the wrasses ( Labridae), in the order Perciformes, but molecular studies have contradicted this ...

s that are endemic to the lake ('' Konia spp.'', ''

Stomatepia ''Stomatepia'' is a genus of cichlids endemic to Lake Barombi Mbo in western Cameroon. Although generally recognized as distinct, the genus is very close to ''Sarotherodon''. The ''Stomatepia'' species are all recognized as critically endangere ...

spp.'', ''

Myaka myaka The myaka (''Myaka myaka'') is a critically endangered species of cichlid endemic to Lake Barombi Mbo in western Cameroon. It prefers open, deeper waters where it feeds on phytoplankton and small insects, only venturing into shallower waters to ...

'', ''

Pungu maclareni The pungu (''Pungu maclareni'') is a species of cichlid endemic to Lake Barombi Mbo in Cameroon where it prefers shallow waters of about in depth. It feeds on invertebrates, sponges, diatoms and macrophytes. This species can reach a length of ...

'', ''

Sarotherodon caroli The fissi (''Sarotherodon caroli'') is a species of cichlid endemic to Lake Barombi Mbo in western Cameroon. This species can reach a length of SL. It is threatened because of pollution and sedimentation due to human activities. It is potenti ...

'', '' S. linnellii'', '' S. lohbergeri'', and '' S. steinbachi'').Schliewen, U.K., Tautz, D., and Pääbo, S. (1994). ''Sympatric speciation suggested by monophyly of crater lake cichlids.''

Nature Nature, in the broadest sense, is the physics, physical world or universe. "Nature" can refer to the phenomenon, phenomena of the physical world, and also to life in general. The study of nature is a large, if not the only, part of science. ...

368(6472): 629–632. These cichlids are commonly recognized as a prime example of

sympatric speciation Sympatric speciation is the evolution of a new species from a surviving ancestral species while both continue to inhabit the same geographic region. In evolutionary biology and biogeography, sympatric and sympatry are terms referring to organi ...

, but studies indicate that they were not the result of a single founding event.Martin; Cutler; Friel; Touokong; Coop; and Wainwright (2015). Complex histories of repeated gene flow in Cameroon crater lake cichlids cast doubt on one of the clearest examples of sympatric speciation. Evolution 69-6: 1406–1422. The lake is strongly

stratified Stratification may refer to: Mathematics * Stratification (mathematics), any consistent assignment of numbers to predicate symbols * Data stratification in statistics Earth sciences * Stable and unstable stratification * Stratification, or st ...

with essentially no oxygen deeper than , meaning that fish are restricted to the upper parts closer to the surface. However, one of the cichlid species, ''

Konia dikume The dikume (''Konia dikume'') is a critically endangered species of fish in the family Cichlidae. It is endemic to Lake Barombi Mbo in western Cameroon. Description The dikume is a silvery coloured fish with faint vertical barring. It grow to a ...

'', has an unusually high level of

hemoglobin Hemoglobin (haemoglobin BrE) (from the Greek word αἷμα, ''haîma'' 'blood' + Latin ''globus'' 'ball, sphere' + ''-in'') (), abbreviated Hb or Hgb, is the iron-containing oxygen-transport metalloprotein present in red blood cells (erythrocyte ...

in its blood, allowing it to briefly enter low-oxygen water to feed on

glassworm ''Chaoborus'' is a genus of midges in the family Chaoboridae. The larvae are known as glassworms because they are transparent. They can be found commonly in lakes all over the world and can be up to . The adults are sometimes called phantom midg ...

s (''Chaoborus''). Other cichlid species in the lake include both generalist and specialist feeders. A highly unusual specialist is ''Pungu maclareni'', which mainly feeds on the endemic

sponge Sponges, the members of the phylum Porifera (; meaning 'pore bearer'), are a basal animal clade as a sister of the diploblasts. They are multicellular organisms that have bodies full of pores and channels allowing water to circulate through t ...

''Corvospongilla thysi''.Steeves, G. (2010)
Insight on Barombi Mbo, Cameroon
Cichlid-forum Retrieved 3 June 2018. All the Barombi Mbo cichlids are

mouth brooder Mouthbrooding, also known as oral incubation and buccal incubation, is the care given by some groups of animals to their offspring by holding them in the mouth of the parent for extended periods of time. Although mouthbrooding is performed by a va ...

s. In addition to the sponge, the lake is home to an endemic species of ''

Caridina ''Caridina'' is a genus of freshwater atyid shrimp. They are widely found in tropical or subtropical water in Asia, Oceania and Africa. They are filter-feeders and omnivorous scavengers. They range from 0.9–9.8 mm ('' C. cantonensis'') t ...

'' shrimp. All the endemic fish are seriously threatened by

pollution Pollution is the introduction of contaminants into the natural environment that cause adverse change. Pollution can take the form of any substance (solid, liquid, or gas) or energy (such as radioactivity, heat, sound, or light). Pollutants, the ...

and

sedimentation Sedimentation is the deposition of sediments. It takes place when particles in suspension settle out of the fluid in which they are entrained and come to rest against a barrier. This is due to their motion through the fluid in response to the ...

from human activities. They are potentially also threatened by large emissions of

carbon dioxide Carbon dioxide (chemical formula ) is a chemical compound made up of molecules that each have one carbon atom covalently double bonded to two oxygen atoms. It is found in the gas state at room temperature. In the air, carbon dioxide is transpar ...

(CO₂) from the lake's bottom (compare

Lake Nyos Lake Nyos ( ) is a crater lake in the Region of Cameroon, located about northwest of Yaoundé, the capital. Nyos is a deep lake high on the flank of an inactive volcano in the Oku volcanic plain along the Cameroon line of volcanic activity ...

), although studies indicate that Barombo Mbo lacks excess amounts of this gas.Freeth, S.J.; C.O. Ofoegbu; and K.M. Onuoha (1992). Natural Hazards in West and Central Africa, pp. 50–51. Commercial fishing is forbidden in the lake. Nevertheless, extensive

subsistence fishing Artisanal fishing (or traditional/subsistence fishing) consists of various small-scale, low-technology, low-capital, fishing practices undertaken by individual fisherman, fishing households (as opposed to commercial fishing). Many of these househ ...

has caused declines in the Barombi Mbo cichlids, but it is shifting to more sustainable practices.

Gallery

File:Lake Barombi, Crater Lake.jpg, Lake Barombi, Crater Lake File:Full extent, Lake Barombi.jpg, Full extent, Lake Barombi File:Lake Barombi, Kumba.jpg, Side view of Lake Barombi, Kumba

References

{{Reflist
CNRS
Barombi Mbo Barombi Mbo Ramsar sites in Cameroon

Biology

Gallery

See also

References