The edges of an iridescent shark's fins have a signature glow
Swai Fish Scientific Classification
- Scientific Name
- Pangasianodon hypophthalmus
Swai Fish Conservation Status
Swai Fish Locations
Swai Fish Facts
- Crustaceans, small fish, and plants
- Group Behavior
- Fun Fact
- The edges of an iridescent shark's fins have a signature glow
- Biggest Threat
- Most Distinctive Feature
- Shark-style dorsal fin
- Other Name(s)
- Tra fish, iridescent shark, pangasius
- Water Type
- Common Name
- Iridescent shark
- Number Of Species
Swai Fish Physical Characteristics
- Skin Type
- 50 - 100 lbs
- 2-4 ft
Swai Fish Images
Click through all of our Swai Fish images in the gallery.
Swai fish, also commonly known as iridescent sharks, are a type of shark catfish that are native to Vietnam.
These omnivorous bottom feeders live in the Mekong river and migrate upstream when the water levels rise in the late summer. When left to their own devices, iridescent sharks can get as big as 100 pounds. Commercial farmers frequently breed large quantities of swai to sell as a popular replacement for catfish meat. You can also find small iridescent sharks that have been stunted in growth to serve as aquarium pets.
3 Incredible Swai Fish Facts!
- Glowing fins: The iridescent shark’s name comes from the edges of its fins, which have a shimmery glow that is visible even in the dark.
- Endless appetite: Swai are known for eating nearly any kind of food they come across. Plants, crustaceans, and smaller fish are no match for the iridescent shark’s omnivorous appetite.
- Sharkfin style: Swai are a type of pangasius, or shark catfish. Although they’re not actually sharks, these catfish all feature a dorsal fin and a silvery, shark-like appearance.
Swai Fish Classification and Scientific Name
The scientific name for swai fish is Pangasianodon hypophthalmus. In Vietnam, they are often referred to as tra fish; they may also be mistaken for the related basa, or Pangasius bocourti. When they’re not being sold as livestock, these silver creatures are frequently called iridescent sharks for their glowing fins and shark-like appearance.
Iridescent sharks belong to the Actinopterygii class and Pangasiidae family of shark catfish. They are related to American catfish, but they are distinguished by their shark-like dorsal fins. In reference to their scientific name, shark catfish are also frequently called pangasius by members of the research community.
Swai Fish Appearance
Iridescent sharks are a type of Asian catfish with silver scales, beige skin, and small whiskers. Like other shark catfish, pangasius have a small dorsal fin on the top of their bodies. The edges of a pangasius’ fins glow faintly underwater, making them a popular choice for aquariums.
Young iridescent sharks can grow to be anywhere from 1 to 4 feet long and typically weigh between 50 to 100 pounds. The largest ever recorded swai fish weight 44 kilograms, or about 97 pounds. The growth of a pangasius can be stunted by diet or a confined space, which is why iridescent sharks that live in aquariums are usually so much smaller than their wild or commercially-grown counterparts.
Swai Fish Distribution, Population, and Habitat
Iridescent sharks are native to Asia and are most commonly found within the country of Vietnam. Most wild pangasius lives in the Mekong river, where they swim upstream from the Maeklong basin. Some pangasius also swims downstream into the Chao Phraya.
Pangasius are freshwater fish and are popularly farmed in ponds, rice paddies, and similar structures. Nearly all commercially sold iridescent sharks are bred as livestock; you shouldn’t expect to purchase a wild pangasius at a normal market. Although population numbers are not available, iridescent sharks are considered to be endangered in their natural habitats.
Swai Fish Predators and Prey
Iridescent sharks are omnivorous animals that feed on crustaceans, algae, bugs, and other small fish. A swai will eat nearly anything it can catch as it grows to its full size of 100 pounds. When they are farmed commercially, pangasius is typically fed a diet that consists of barley, oats, and other types of grain.
Pangasius has no natural means of self-defense, making them a popular target for all predatory animals in their native region, including birds, mammals, and other large fish. Human fishermen are one of the primary threats to iridescent sharks, and overfishing is likely responsible for their current status of endangered.
Swai Fish Reproduction and Lifespan
Iridescent sharks are egg-laying creatures that live in large clusters. Like other types of catfish, pangasius breed in a migratory pattern that involves swimming upstream to a breeding ground during the late summer months.
Due to their wild nature, iridescent sharks are particularly difficult to breed in captivity. Pangasius farmers tend to keep the fish in large ponds with many other members of the same species to ensure adequate breeding conditions. Due to the lack of research on this particular type of fish, it is unknown how long a swai might live in the wild. In captivity, a well-loved iridescent shark might manage to have a lifespan as long as twenty years.
Swai Fish in Fishing and Cooking
Although iridescent sharks are found naturally in the rivers of Vietnam, most commercial swai production takes place in controlled farming environments. Large groups of pangasius are kept in ponds, rice fields, and other watery areas until they are big enough to harvest for consumption.
In cooking, swai meat is used as a popular replacement for American catfish. The taste is described as sweet and significantly milder than their catfish cousins. Swai is known to have a tougher texture and slightly blander taste than basa, another shark catfish that is found in the same region.
Swai meat is a good source of nutrition with plenty of protein and vitamin B12. Unless you live in Vietnam, you are most likely to find pangasius meat in the frozen section, where it can stay fresh and delicious for up to a year at a time. Frozen pangasius meat can be baked, broiled, or fried to achieve the best taste. Just remember to thaw your frozen fish out before you cook it to prevent too much moisture from entering the dish.View all 78 animals that start with S
Swai Fish FAQs (Frequently Asked Questions)
Where is swai fish found?
Wild iridescent sharks are found throughout Asia, but they are considered native to the Mekong River in Vietnam. Commercial pangasius is typically kept in ponds and other types of local fish farms.
What is swai fish?
The iridescent shark is a type of catfish native to Vietnam. Swai meat is often sold as a popular replacement to American catfish or the slightly more expensive basa fish.
Is swai fish high in mercury?
Iridescent sharks have a relatively low mercury content. A study of commercially available pangasius only found a mercury content of 2 parts per billion.
Is swai fish banned?
As long as they are labeled correctly, iridescent sharks are not banned for sale or consumption anywhere in the first world. However, it is illegal to market pangasius as catfish in the United States.
Is swai fish safe to eat?
Swai meat is considered safe to eat and is a popular protein choice in many markets. However, be aware that any aquatic meat may be subject to questionable farming practices and should be purchased with consumer discretion.
Is swai fish healthy?
Swai meat is a relatively healthy protein choice for most diets. Pangasius meat contains high amounts of selenium, niacin, and vitamin B12.
Swai fish vs. Basa fish
Swai and basa are both types of shark catfish that are native to Vietnam. Basas, also known as Pangasius bocourti, are rarer than swai; they are also larger and typically have softer and more tender meat. Swai is often mislabeled as bocourti in some markets.
Are Swai Fish herbivores, carnivores, or omnivores?
Swai Fish are Omnivores, meaning they eat both plants and other animals.
What Kingdom do Swai Fish belong to?
Swai Fish belong to the Kingdom Animalia.
What phylum do Swai Fish belong to?
Swai Fish belong to phylum Chordata.
What class do Swai Fish belong to?
Swai Fish belong to the class Actinopterygii.
What family do Swai Fish belong to?
Swai Fish belong to the family Pangasiidae.
What order to Swai Fish belong to?
Swai Fish belong to order Siluriformes.
What type of covering do Swai Fish have?
Swai Fish are covered in Scales.
What type of covering do Swai Fish have?
Swai Fish are covered in Scales.
- VASEP, Available here: http://mseafood.vasep.com.vn/panga/724_10857/what-are-biology-characteristics-of-tra-and-basa-fish.htm
- Seafood Handbook, Available here: https://www.seafoodsource.com/seafood-handbook/finfish/basaswai
- Fishbase, Available here: http://www.fishbase.us/summary/SpeciesSummary.php?ID=14154&AT=swai
- Fish Laboratory, Available here: https://www.fishlaboratory.com/fish/swai-fish
- National Library of Medicine, Available here: https://pubmed.ncbi.nlm.nih.gov/25198598/