Flathead Catfish Species Information

Flathead Catfish - Pylodictis olivaris

As the common name suggests, this catfish has a flat head, but other than that, it looks like any other catfish: it has smooth, scaleless skin, whisker-like barbels around the mouth, and long spines on the dorsal (back) fin and one on each side of the pectoral (shoulder) fin. Flathead catfish reach a length of 3 to 4 feet (0.9 to 1.2 m) and their weight can exceed 100 pounds (45 kg). Pylodictis is Greek meaning "mud fish", and olivaris is Latin for "olive-colored". Flathead catfish are typically pale yellow (hence the name "yellow cat") to light brown on the back and sides, and highly mottled with black and/or brown. The belly is usually pale yellow or cream colored. The head is broadly flattened, with a projecting lower jaw. The tail fin is only slightly notched, not deeply forked as is the case with blue and channel catfish. Young fish may be very dark, almost black in appearance. 

Geographic Range

Flathead catfish are native to rivers and lakes in the lower Great Lakes and Mississippi River basin. They are found in appropriate habitat in Texas, Louisiana, Arkansas, Oklahoma, Arkansas, Missouri, Kansas, much of Nebraska, South Dakota, North Dakota, Iowa, Minnesota, Illinois, Indiana, Ohio, Kentucky, western Virginia, Tennessee, Alabama, and as far south as Mexico.

This species has been introduced farther east and west of its native range, to parts of Washington, Oregon, California, Arizona, New Mexico, Wyoming, Colorado, Georgia, South Carolina, North Carolina, Virginia, and Pennsylvania.

• Biogeographic Regions: Nearctic, introduced, native

Physical Description

This is a large-bodied species that can attain sizes of over one meter in length and 56 kg in weight. Flathead catfish are also called mud catfish, because of their yellow to purple-brown dorsal coloration. The belly is pale white to yellow. Not surprisingly, their head is wider and flatter than that of other North American catfishes. The lower jaw protrudes farther out than the upper jaw, with the mouth having a wide oval shape. The caudal fin has rounded to slightly notched posterior margin, and a white tip on the upper lobe (except in large adults), which can be used to distinguish this species from other members of the family Ictaluridae. Flathead catfish have both pectoral and dorsal-fin spines. The anal fin is short and rounded in profile, and contains 14-17 elements. There is no externally discernible physical difference between males and females.

• Range mass: 0.5 to 56.7 kg/1.10 to 124.89 lb
• Average mass: 20.4 kg/44.93 lb
• Range length: 38.1 to 114.3 cm/15.00 to 45.00 in

Life Span

5 - 20 years

Habitat

Flathead catfish inhabit rivers, lakes, and reservoirs with slow currents. Younger individuals prefer shallower water. Older and larger flathead catfish stay in deeper waters during the daylight hours (typical depth 3-6 m), moving into shallower water at night. They prefer to remain near or under cover, including fallen trees, logs, brush piles, and river banks. A log that is 5 m long is large enough to provide sufficient cover for one large adult flathead catfish. These catfish are generally found in waters from 21.7 to 30°C.

• Habitat Regions: temperate freshwater
• Aquatic Biomes: lakes and ponds, rivers and streams
• Range depth: 3 to 6 m/9.84 to 19.69 ft

Lifespan/Longevity

Flathead catfish can live up to 28 years, although the typical lifespan is 5 to 22 years, based on pectoral spine and otolith age estimates. Due to the large size of adults, this species is not commonly kept in captivity.

• Range lifespan Status: wild 28 (high) years
• Typical lifespan Status: wild 5 to 22 years

Home Range

Individual home ranges vary throughout the year. In a study in a southwest Michigan river, seasonal differences in movement were pronounced. During the spring, which is the most active time of the year, the average home range was 1,513 m of stream. In the summer months, the catfish being studied moved an average of 596 m upstream or downstream. During the fall, the average home range was 1,250 m of stream. Since these catfish are inactive during the winter, their home range at that time is presumably much reduced, although it was not explicitly measured. 

Sport fishing

Sport fishing for flathead catfish using either rod and reel, limb lines, or bare hands (noodling) can be an exciting pastime. Anglers target this species in a variety of waterways, including small rivers (barely large enough for a canoe), large rivers (such as the Missouri, Mississippi, Ohio, Tennessee and Colorado Rivers), and reservoirs. A common element of flathead catfish location is submerged wood cover such as logs and rootwads which often collect at bends in rivers. A good flathead spot usually also includes relatively deep water compared to the rest of a particular section of river, a moderate amount of current, and access to plentiful baitfish such as river herring, shad, carp, drum, panfish, or suckers. Anglers targeting large flathead catfish usually use stout tackle such as medium-heavy or heavy action rods from 6–10 ft (1.8–3.0 m) in length with large line-capacity reels and line ranging from 20–80 pounds-force (89–356 N) test breaking strength. Generally large live baits are preferred such as river herring, shad, sunfish (such as bluegill), suckers, carp, goldfish, drum, and bullheads ranging from 5–12 in (13–30 cm) in length.

Similar species

Other large catfishes, including the Channel Catfish, Ictalurus punctatus, and Blue Catfish, I. furcatus, lack the mottled color pattern of the Flathead, the white tip on the upper lobe of the caudal fin, and the projecting lower jaw.