Boal
Large freshwater catfish native to South and Southeast Asia.
The boal is a predatory freshwater catfish found across the Indian subcontinent and parts of Southeast Asia. It reaches lengths of up to 1.1 metres and serves as a traditional food source in Thailand, where its meat is used for fish cakes.
- Reaches a maximum length of 1.1 metres
- Diet consists of 90 to 95 per cent animal matter
- Used in Thailand to make traditional fish cakes
- Has a disjunct distribution across Asia
What it is
The boal is a large species of freshwater catfish belonging to the family Siluridae. It features a relatively long and narrow head with eyes positioned above the mouth. The dorsal fin is high and sharp, distinguishing it from similar species. Adults can grow up to 1.1 metres in length. This fish inhabits large river systems and lakes across two separate geographic regions in Asia.
Where it lives
This species has a disjunct distribution, meaning its populations are separated by a significant gap. One group lives across the Indian subcontinent, including rivers in India, Pakistan, Bangladesh, Nepal, Bhutan, Sri Lanka, Iran, and Afghanistan. The other population resides in Southeast Asia, covering Thailand, Laos, Cambodia, Vietnam, Malaysia, and Indonesia. It is notably absent from the Salween and Tenasserim drainages in Burma, as well as the island of Borneo.
How it lives
As a large predator, the boal maintains a diet consisting almost entirely of other fish. Studies of stomach contents in the Godavari river show that animal matter makes up 90 to 95 per cent of its food. Common prey includes small species such as razorbelly minnows, ticto barbs, and perchlets. These target fish typically reach maximum lengths of only 10 to 12 centimetres.
Fish and people
People in Southeast Asia have consumed this catfish since ancient times. In Thailand, the meat is a popular ingredient for thot man, which are Thai fish cakes. In Malaysia and Indonesia, it is known as ikan tapah. Local folklore in Malaysia tells of a man named Tok Kaduk who found gold inside one. His descendants are said to suffer itchy skin if they touch the fish, requiring a cure made from the remaining gold.
Status and threats
Biologists state that this species does not grow beyond roughly one metre. Reports of larger specimens often confuse it with the related Wallagonia leerii, which can reach twice the length. The authenticated angling record stands at 18 kg, caught in a Thai reservoir. Some breeding ponds claim to hold larger individuals, but wild records remain lower than those of its larger relative.
Questions people ask about Boal
How big does the boal catfish get?
This species can reach a length of up to 1.1 metres. Biologists confirm it does not grow beyond roughly one metre in the wild, despite claims of larger sizes which usually refer to a different species.
What does the boal eat?
It is a predatory fish with a largely piscivorous diet. Gut analysis shows that 90 to 95 per cent of its food is animal matter, primarily small fish like minnows, barbs, and perchlets.
Why is it called helicopter catfish?
Both Wallago attu and the similar Wallagonia leerii are sometimes called helicopter catfish in English. This name is used in popular accounts and by fishermen, though it often leads to confusion between the two distinct species.
Good reading and sources
The facts on this page come from the Wikipedia article "Wallago attu", written by its contributors and used under the CC BY-SA 4.0 licence, and from its Wikidata record (CC0). EveryFish rewrote the text in its own words, with AI assistance, and compares every page with the article to make sure no passage is copied. It may be reused under the same CC BY-SA 4.0 licence with a link back.
It may contain mistakes, and figures change over time. Nothing here is investment or buying advice. If something is wrong, tell us. Last refreshed 2026-11-15.
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