In the vast underwater realms, catfish reign supreme as fascinating and diverse creatures. From gentle giants that can grow to astonishing sizes to small, agile species that charm us with their unique traits, catfish offer an abundance of surprises for both anglers and nature enthusiasts alike.
With over 30 catfish species thriving in the United States alone, and a whopping 3,000 worldwide, there’s no shortage of surprises. And, of course, there’s also a wide range of sizes when it comes to catfish. In this article, we will rank 10 of these incredible creatures by size.
1. Wels Catfish (Silurus glanis) — Up to 15 Feet
The wels catfish, often overshadowed by its more famous relative, the Mekong giant catfish, actually holds the title of the largest type of catfish.
These incredible fish can grow to impressive dimensions, with lengths stretching up to 15 feet and weighing anywhere from 300 to 660 pounds.
They possess distinctive features such as long, broad heads, slender bodies, wide mouths, and notably long and slender barbels. With four shorter ones on their lower jaw and two barbels on their upper jaw, Wels catfish utilize these appendages to hunt and detect their prey.
These impressive catfish typically inhabit lowland rivers, backwaters, and well-vegetated lakes, although they may occasionally venture into brackish water. Despite their remarkable size, Wels catfish are surprisingly agile in their aquatic habitats. They have a diverse diet, consuming various prey, including fish, crayfish, mollusks, birds, and even small mammals.
Surprisingly, eating wels catfish can have potential health risks. As they occupy the top of the food chain, they accumulate toxins from the numerous fish they consume, making their flesh potentially poisonous to humans.
Nonetheless, these colossal catfish play an important role in maintaining the ecological balance of their habitats, showcasing their significance in the natural world.
2. Piraiba (Brachyplatystoma filamentosum) — Up to 12 Feet
Legend has it that the piraiba, a fearsome creature dwelling in the Amazon, has a voracious appetite for men. However, rest assured, this notion remains confined to ancient tales and folklore.
The piraiba, an aquatic behemoth, can grow up to nearly 12 feet in length and weigh over 400 pounds. Despite its colossal size, this catfish is surprisingly agile and lightning-fast, capable of leaping out of the water to snatch its prey.
This formidable fish exclusively inhabits the Amazon and is the largest catfish found in the river. A white underside complements its sleek, silvery-gray body, while its lips occasionally boast a reddish hue. The piraiba possesses smooth, scale-free skin and has long maxillary barbels extending well beyond its dorsal fin, occasionally almost reaching its caudal fin.
When it comes to food, the piraiba is an indiscriminate eater. Inside its stomach, fishermen have discovered various creatures ranging from monkeys and birds to other catfish.
These magnificent creatures are known for their extensive migration, traversing vast distances from the Amazon estuaries to the headwaters nestled in the foothills of the Andes.
Only the bravest and most tenacious anglers dare to target the piraiba due to its immense size and strength!
3. Mekong Giant Catfish (Pangasianodon gigas) — Up to 10 Feet
Among the renowned species of large catfish, the Mekong giant catfish stands out as the third largest catfish in the world. These magnificent creatures possess a white-to-gray coloration and lack distinctive stripes. Their eyes are set low, giving them a somewhat melancholic appearance. What sets them apart from other large catfish species is their unique feature: they have very few if any, barbels or “whiskers,” and they do not possess teeth.
Comparable in size to a grizzly bear, the largest recorded Mekong giant catfish measured approximately 10 feet long and weighed a staggering 646 pounds.
The Mekong giant catfish is exclusively found in the lower regions of the Mekong River in Southeast Asia. Despite its formidable size, this gentle giant poses minimal threat to other species. It is predominantly herbivorous, subsisting on a diet consisting mainly of algae and different plant life that grow on the riverbed.
Conservationists have recognized the importance of the Mekong giant catfish as a flagship species for promoting river conservation. In order to safeguard this critically endangered species, harvesting the giant catfish has been declared illegal in Laos, Cambodia, and Thailand. However, there are still instances of illegal fishing, with some individuals selling these magnificent creatures to restaurants in Vietnam.
4. Goonch (Bagarius yarrelli) — Up to 6.6 Feet
Another notable catfish on the list is the goonch, also referred to as the giant devil catfish. It is a sizable species found in rivers throughout the Indian subcontinent.
The goonch catfish can be identified by its pale grey or yellow-brown coloration, often accompanied by a distinctive black patch. The head of the fish is adorned with sensory pores, while its body lacks scales and instead has a slimy texture.
Growing up to 6.6 feet in length, the goonch catfish is a formidable predator and the fourth largest catfish on our list. The goonch’s diet primarily comprises smaller fish, crustaceans, amphibians, and a variety of invertebrate species. Thriving in swiftly-flowing currents, this species calls mountainous rivers its home.
While still relatively abundant, the goonch catfish is categorized as vulnerable on the IUCN Red List. The primary reason for this vulnerability is the excessive and unsustainable overharvesting of the species. Moreover, the development of hydroelectric projects, like those found on the Indravati River, presents a potential danger to their natural environment, potentially causing detrimental impacts on the species.
5. Sharptooth Catfish (Clarias gariepinus) — Up to 5 Feet 7 Inches
Ranked fifth among the largest catfish species, the sharptooth catfish has a distinct appearance. Its slimy, elongated body showcases a mottled brown to green or gray coloration, complemented by a wide, flat, and compressed head. This catfish has small, dark eyes and an impressive array of four pairs of sensory whiskers, known as barbels.
Reaching a maximum length of 5 feet 7 inches and weighing up to 130 pounds, the sharptooth catfish is a resilient species capable of adapting to various habitats. While it can thrive in almost any environment, it prefers floodplains, lakes, dams, and rivers.
Being completely omnivorous, the sharptooth catfish has a versatile diet. It opportunistically feeds on a wide range of organic food sources, including insects, birds, fish, frogs, crabs, small mammals, shrimps, and other invertebrates.
Not only is the sharptooth catfish abundant and widely consumed as a food source throughout Africa, but it also offers the advantage of having few bones, making it a delectable option for culinary purposes.
6. Blue Catfish (Ictalurus furcatus) — Up to 5 Feet
In the United States, the blue catfish stands out as a well-known species and ranks as the sixth largest catfish globally. It features a deeply forked tail and a flat dorsal fin, presenting a distinct appearance. With a silvery-blue hue on its body and a white underside, the blue catfish exhibits smooth, scale-free skin. Notably, it has four pairs of black whisker-like barbels surrounding its mouth.
While typically growing to be under 2 feet in length, blue catfish have the potential to reach an impressive size of 5 feet and weigh over 100 pounds. These bottom-dwelling creatures thrive in swift currents, sandy bottoms, and large rivers with deep channels. While they prefer freshwater environments, blue catfish can adapt to higher salinities.
Their voracious appetite leads them to consume a variety of prey, including other fish, crustaceans, and even fellow catfish. Unfortunately, their robust feeding habits can lead to competition with native species for both habitat and food.
Despite their impact on the ecosystem, blue catfish are highly regarded for their culinary value. As the largest catfish species in North America, they make for a delightful and healthy meal.
7. Redtail Catfish (Phractocephalus hemioliopterus) — Up to 5 Feet
The redtail catfish possesses remarkable chemosensory and tactile abilities, which it employs to detect prey in its surroundings.
This catfish boasts a broad head adorned with long whiskers, along with a dark black body and a contrasting white underside that extends from its mouth to the caudal fin. Notably, its distinctive red tail may be accompanied by red-colored dorsal, pelvic, and anal fins.
Reaching lengths of 5 feet or more and weighing up to 180 pounds, redtail catfish are highly sought after as game fish in their natural habitats. They exclusively inhabit freshwater environments, favoring larger rivers, streams, and lakes.
Redtail catfish are known for their territorial nature. When it comes to their diet, they consume a variety of prey, including fish, crustaceans, and fallen fruits.
These captivating catfish are quite popular in the aquarium trade due to their striking appearance and resilient disposition. However, it is important to note that they can grow over 3 feet in length, requiring a spacious tank with robust filtration. While generally peaceful, they may consume smaller tank mates, so careful consideration is necessary when selecting compatible tank companions.
8. Jau Catfish (Zungaro zungaro) — Up to 5 Feet
The jau catfish, often referred to as the “sumo wrestlers” of the Amazon, possesses a tough and formidable nature, rivaling its counterparts, the retail and piraiba catfish.
Sporting a dark brown coloration with a lighter belly, the jau catfish displays subtle darker spots on its head and upper body. Notably, it features just one long whisker on each side of its mouth, while its fins are adorned with long, threadlike strands at the ends, aiding in swift maneuverability.
Also known as the gilded catfish, this river monster can grow up to an impressive 5 feet in length and weigh around 200 pounds.
The jau catfish thrives in well-oxygenated water and is commonly found in rocky areas below falls and rapids, where it seeks refuge. Its diet consists of various prey items, including fish, squid, shrimp, and frogs. It even acts as a scavenger, consuming almost any available food source.
The jau catfish holds great importance as a food fish in the areas where it is found. However, it faces significant challenges. With its limited range and various threats, the jau catfish has been classified as an endangered species.
9. Tiger Catfish (Pseudoplatystoma fasciatum) — Up to 4.5 Feet
The tiger catfish is a remarkable freshwater fish that has quickly gained popularity among aquarists. Impressive in size, it claims the 9th position on this list of the largest catfish species.
In captivity, it can grow to over 3 feet in length. Sporting a long and slender body, the tiger catfish is a stunning silver in color and adorned with black stripes and spots, resembling the majestic appearance of a tiger.
In the wild, tiger catfish can reach lengths of up to 4.5 feet and weigh around 88 pounds. These captivating fish originate from the rivers of South Africa. Feeding the tiger catfish is hassle-free, as it is not a picky eater. In its natural habitat, it consumes fish and crustaceans. In an aquarium setting, providing a balanced diet is easily achieved with a variety of food options such as frozen foods, assorted worms, dry foods, and sinking catfish pellets.
Beyond their popularity among aquarists, tiger catfish have also become highly sought after as a sport fish. Once hooked, they put up a strong fight, staying close to the bottom and remaining deep until the very end. Landing a tiger catfish is not only thrilling but also rewarding, as their stunning appearance makes for impressive photos and admiration.
10. Flathead Catfish (Pylodictis olivaris) — Up to 4 Feet
The flathead catfish is a widely recognized species that needs no introduction. It is the second-largest catfish in North America, trailing only behind the blue catfish in size.
With their distinct appearance, flathead catfish are typically pale yellow in color, earning them the nickname “yellow cat,” and exhibit mottled patterns of brown and/or black. Their broad, flattened heads feature a prominent lower jaw, adding to their unique charm.
Growing to lengths of 3 to 4 feet and weighing over 100 pounds, flathead catfish are formidable in size. They favor deep pools found in rivers, lakes, streams, canals, and reservoirs, where the currents are gentle and the water is cloudy.
Not only are flathead catfish popular among anglers for their size and sporting qualities, but their flesh is also highly regarded for its delectable taste. In fact, it is widely considered the most flavorful among all catfish species. Furthermore, their impressive size makes flathead catfish captivating attractions in public aquariums.
Summary of Types of Catfish Ranked by Size
|Size (up to)
|Amazon & Orinoco River
|Giant Mekong Fish
|Mekong Basin (Asia)
|5 Feet 7 Inch
|Amazon & Orinoco River
The photo featured at the top of this post is © tristan tan/Shutterstock.com
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