The giant barb, Siamese Giant carp, or simply Siamese carp (''Catlocarpio siamensis''; , ; , , , or , , ;

Vietnamese Vietnamese may refer to: * Something of, from, or related to Vietnam, a country in Southeast Asia * Vietnamese people, or Kinh people, a Southeast Asian ethnic group native to Vietnam ** Overseas Vietnamese, Vietnamese people living outside Vietna ...

: ''cá Hô'') is the largest species of

cyprinid Cyprinidae is a Family (biology), family of freshwater fish commonly called the carp or minnow family, including the carps, the true minnows, and their relatives the barb (fish), barbs and barbel (fish), barbels, among others. Cyprinidae is the ...

in the world. These migratory fish are found only in the

Mae Klong The Mae Klong (, , ), sometimes spelled Meklong, is a river A river is a natural stream of fresh water that flows on land or inside Subterranean river, caves towards another body of water at a lower elevation, such as an ocean, lake, o ...

Mekong The Mekong or Mekong River ( , ) is a transboundary river in East Asia and Southeast Asia. It is the world's twelfth-longest river and the third-longest in Asia with an estimated length of and a drainage area of , discharging of wat ...

, and

Chao Phraya The Chao Phraya River is the major river in Thailand, with its low alluvial plain forming the centre of the country. It flows through Bangkok and then into the Gulf of Thailand. Etymology Written evidence of the river being referred to by the ...

River basins in

Indochina Mainland Southeast Asia (historically known as Indochina and the Indochinese Peninsula) is the continental portion of Southeast Asia. It lies east of the Indian subcontinent and south of Mainland China and is bordered by the Indian Ocean to th ...

. Populations have declined drastically due to

habitat loss Habitat destruction (also termed habitat loss or habitat reduction) occurs when a natural habitat is no longer able to support its native species. The organisms once living there have either moved elsewhere, or are dead, leading to a decrease ...

and

overfishing Overfishing is the removal of a species of fish (i.e. fishing) from a body of water at a rate greater than that the species can replenish its population naturally (i.e. the overexploitation of the fishery's existing Fish stocks, fish stock), resu ...

, and the giant barb is now considered

critically endangered An IUCN Red List critically endangered (CR or sometimes CE) species is one that has been categorized by the International Union for Conservation of Nature as facing an extremely high risk of extinction in the wild. As of December 2023, of t ...

Distribution and habitat

Giant barbs are usually seen in large pools along the edges of large rivers, but seasonally enter smaller

canal Canals or artificial waterways are waterways or engineered channels built for drainage management (e.g. flood control and irrigation) or for conveyancing water transport vehicles (e.g. water taxi). They carry free, calm surface ...

floodplain A floodplain or flood plain or bottomlands is an area of land adjacent to a river. Floodplains stretch from the banks of a river channel to the base of the enclosing valley, and experience flooding during periods of high Discharge (hydrolog ...

s, and flooded forests. Young barbs are usually found in smaller

tributaries A tributary, or an ''affluent'', is a stream or river that flows into a larger stream ('' main stem'' or ''"parent"''), river, or a lake. A tributary does not flow directly into a sea or ocean. Tributaries, and the main stem river into which the ...

and

swamp A swamp is a forested wetland.Keddy, P.A. 2010. Wetland Ecology: Principles and Conservation (2nd edition). Cambridge University Press, Cambridge, UK. 497 p. Swamps are considered to be transition zones because both land and water play a role in ...

s, but can acclimate to living in

pond A pond is a small, still, land-based body of water formed by pooling inside a depression (geology), depression, either naturally or artificiality, artificially. A pond is smaller than a lake and there are no official criteria distinguishing ...

s, and

s. The fish generally live in pairs. These are migratory fish, swimming to favorable areas for feeding and breeding in different parts of the year. These slow-moving fish subsist on

algae Algae ( , ; : alga ) is an informal term for any organisms of a large and diverse group of photosynthesis, photosynthetic organisms that are not plants, and includes species from multiple distinct clades. Such organisms range from unicellular ...

phytoplankton Phytoplankton () are the autotrophic (self-feeding) components of the plankton community and a key part of ocean and freshwater Aquatic ecosystem, ecosystems. The name comes from the Greek language, Greek words (), meaning 'plant', and (), mea ...

, and

fruit In botany, a fruit is the seed-bearing structure in flowering plants (angiosperms) that is formed from the ovary after flowering. Fruits are the means by which angiosperms disseminate their seeds. Edible fruits in particular have long propaga ...

s of inundated

terrestrial plant A terrestrial plant is a plant that grows on, in or from land. Other types of plants are aquatic plant, aquatic (living in or on water), semiaquatic (living at edge or seasonally in water), epiphyte, epiphytic (living on other plants), and litho ...

s, rarely (if ever) feeding on active

animal Animals are multicellular, eukaryotic organisms in the Biology, biological Kingdom (biology), kingdom Animalia (). With few exceptions, animals heterotroph, consume organic material, Cellular respiration#Aerobic respiration, breathe oxygen, ...

s. In the lower Mekong basin, young giant barbs have been reported as occurring primarily in October.

Physical characteristics

The head is rather large for the body, with no

barbel Barbel may refer to: *Barbel (anatomy), a whisker-like organ near the mouth found in some fish (notably catfish, loaches and cyprinids) and turtles *Barbel (fish), a common name for certain species of fish **''Barbus barbus'', a species of cyprini ...

s. The giant barb ranks among the largest freshwater fish in the world, and is probably the largest fish in the family

Cyprinidae Cyprinidae is a family of freshwater fish commonly called the carp or minnow family, including the carps, the true minnows, and their relatives the barbs and barbels, among others. Cyprinidae is the largest and most diverse fish family, and t ...

.Nelson, Joseph S. (2006). ''

Fishes of the World ''Fishes of the World'' is a standard reference for the systematics of fishes. It was first written in 1976 by the American ichthyologist Joseph S. Nelson (1937–2011). Now in its fifth edition (2016), the work is a comprehensive overview of t ...

''. John Wiley & Sons, Inc. It may reach (although this claimed maximum length needs confirmation) and weigh up to . Among the cyprinids, only the golden mahseer can reach a comparable length, but it is a relatively slender fish that weighs far less. Few large giant barbs are caught today. For example, no individual weighing more than has been caught in

Cambodia Cambodia, officially the Kingdom of Cambodia, is a country in Southeast Asia on the Mainland Southeast Asia, Indochinese Peninsula. It is bordered by Thailand to the northwest, Laos to the north, and Vietnam to the east, and has a coastline ...

since 1994. Today, the maximum length is about . The current record weight is 105 kg for an individual caught in Thailand in 2019 breaking the previous record by 5 kg. This fish is a

tetraploid Polyploidy is a condition in which the cells of an organism have more than two paired sets of ( homologous) chromosomes. Most species whose cells have nuclei (eukaryotes) are diploid, meaning they have two complete sets of chromosomes, one fro ...

, meaning it has four of each chromosome (as opposed to

diploid Ploidy () is the number of complete sets of chromosomes in a cell, and hence the number of possible alleles for autosomal and pseudoautosomal genes. Here ''sets of chromosomes'' refers to the number of maternal and paternal chromosome copies, ...

, the normal number in animals).

Conservation

Today, few barbs live to maturity. The main threats are habitat loss (e.g.,

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

and

dam A dam is a barrier that stops or restricts the flow of surface water or underground streams. Reservoirs created by dams not only suppress floods but also provide water for activities such as irrigation, human consumption, industrial use, aqua ...

s) and overfishing. The sharp population decline is well illustrated by catch data from Cambodia, where 200 tonnes of giant barbs were caught in 1964. By 1980, only about 50 fish were caught, and by 2000, only 10. It was formerly an important fish in local catches below the Khone Phapheng Falls, but surveys between 1993 and 1999 only located a single small individual. Consequently, the giant barb is listed as

Critically Endangered An IUCN Red List critically endangered (CR or sometimes CE) species is one that has been categorized by the International Union for Conservation of Nature as facing an extremely high risk of extinction in the wild. As of December 2023, of t ...

on the

IUCN Red List The International Union for Conservation of Nature (IUCN) Red List of Threatened Species, also known as the IUCN Red List or Red Data Book, founded in 1964, is an inventory of the global conservation status and extinction risk of biological ...

. It has been entirely

extirpated Local extinction, also extirpation, is the termination of a species (or other taxon) in a chosen geographic area of study, though it still exists elsewhere. Local extinctions are contrasted with global extinctions. Local extinctions mark a chan ...

from the

Chao Phraya River The Chao Phraya River is the major river in Thailand, with its low alluvial plain forming the centre of the country. It flows through Bangkok and then into the Gulf of Thailand. Etymology Written evidence of the river being referred to by the ...

. In a 2005 royal decree, the Kingdom of Cambodia designated this fauna as the national fish to bring conservation awareness to this species. In 2005, the giant barb was successfully domesticated and reproduced for the first time at the Vietnam National Breeding Center for Southern Freshwater Aquaculture. In 2010, the Vietnam National Breeding Center released 50,000 young giant barbs into the Tien River in Dong Thap province Vietnam, but a later survey showed that only a few of them survived long enough to reach a weight of over one kilogram. In 2012, it was successfully reproduced in the Breeding Center of An Giang Province of Vietnam.

Cultivation

In recent years, raising giant barb has become common in Vietnam due to its high economic value. Two breeding centers in southern Vietnam offer about 1 million breeder giant barbs to farmers per year. When kept in floating cages in rivers, the fish grow fast and gain 7 kg to 9 kg per year. In ponds where the main diet is natural algae, the fish gain 2 to 5 kg per year. Usually, giant barbs are harvested after three years of cultivation when they weigh 6 to 10 kg, but some farmers keep raising their fish in ponds for more than seven years for them to reach 50 kg before harvesting.

References

External links

Photo in ''National Geographic'' of a large specimen
{{DEFAULTSORT:Giant Barb Probarbinae Cyprinid fish of Asia Fish of Cambodia Fish of Thailand National symbols of Cambodia Fish described in 1898