Giant Carp
CR

Giant Carp

Catlocarpio siamensis

Declining

Photo: Photo: Wikimedia Commons, CC BY-SA

Overview

The giant barb, Siamese giant carp, or simply Siamese carp is the largest species of cyprinid, and may also be the largest member in the suborder Cyprinoidei. These migratory fish are found only in the Mae Klong, Mekong, and Chao Phraya River basins in Indochina. Populations have declined drastically due to habitat loss and overfishing, and the giant barb is now considered critically endangered.

The Giant Barb faces severe population decline primarily due to overfishing and dam construction across the Mekong River system. Large-scale hydroelectric projects have fragmented its habitat and disrupted critical spawning migrations, while intensive fishing pressure targets this species for its commercial value. Water pollution from agricultural runoff and industrial activities further degrades the aquatic ecosystems this massive freshwater fish depends upon.

Threat summary

Habitat

Catlocarpio siamensis inhabits large rivers and associated floodplains throughout the Mekong River basin, particularly in Thailand, Laos, Cambodia, and Vietnam. This species requires deep pools and flowing waters for feeding and undertakes extensive migrations to flooded forests and grasslands for spawning during the wet season.

Wetlands (inland)· majorWetlands (inland) - Permanent rivers/streams· majorWetlands (inland) - Permanent freshwater lakes· major

Conservation measures underway

Site/area protectionSpecies recoveryLegislation

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Frequently asked questions

Why is Giant Carp classified as Critically Endangered?
Giant Carp is classified as Critically Endangered — facing an extremely high risk of extinction in the wild — because population sizes are very small, declining sharply, or restricted to a tiny range. The Giant Barb faces severe population decline primarily due to overfishing and dam construction across the Mekong River system. Large-scale hydroelectric projects have fragmented its habitat and disrupted critical spawning migrations, while intensive fishing pressure targets this species for its commercial value. Water pollution from agricultural runoff and industrial activities further degrades the aquatic ecosystems this massive freshwater fish depends upon.
Where does Giant Carp live?
Giant Carp occurs in Cambodia, Laos, Thailand, and Vietnam. Country-level distribution data is sourced from the IUCN Red List and cross-referenced with GBIF occurrences.
What are the main threats to Giant Carp?
The main threats to Giant Carp are 1.1, 2.1, 5.3, and 5.4. The full IUCN-classified threat record for this species is detailed on the species page.

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