Flathead catfish
Pylodictis olivaris (Rafinesque, 1818)

member of the Catfish Family (Ictaluridae)

St. Croix River, Washington County, Minnesota Summer 1976

young of the year

photos by Konrad Schmid













What's In a Name?
Flathead catfish: refers to the flattened appearance of the head of the catfish

Pylodicitis (pie-low-dick´-tiss) means "mud fish" in Greek
olivaris (oh-lee-vair´-iss) means "olive-colored" in Latin

    Where Do They Live?
Fathead catfish are found in the southeastern quarter of Minnesota. They are most common in the lower Mississippi, Minnesota, and lower St. Croix rivers. Young flatheads often live among rocks in a slight current, while the adults prefer to live in deep pools, backwaters, and other sheltered places in the sluggish parts of rivers. The flathead is a bottom-dwelling species.


How Big Do They Get?
How Long Do They Live?
Flathead catfish are one of Minnesota's largest fish. Large flatheads grow over 1 m (3.2 ft) long and can weigh over 23 kg (50 lbs). The Minnesota hook and line record is an amazing 31.8-kg (70 lbs). This is the second biggest state record fish (the first is a 42.9-kg (94 lbs, 4 oz) lake sturgeon). This shy and private fish can easily reach the age of 12-14 years old, but there are records of flatheads attaining the ripe old age of 24 years old.

    What Do They Eat?
Flathead catfish are mainly a "lie-in-wait" predator. They rest on the bottom by large rocks, logs, or other debris, often with their mouths open. When other fish swim near, they grab them with their huge mouths. They will eat any fish that makes the mistake of getting too close. Young flatheads eat a variety of aquatic insects, crayfish, small fish, and worms, but they soon move on to eating fish. Unlike bullhead and channel catfish, flatheads rarely eat dead or decaying animal matter.

What Eats Them?
Bullheads, channel catfish, and other piscivorous (fish-eating) fishes commonly eat the young flatheads. Flatheads grow rapid though, and they soon become too large for most predators to handle. Since many people like the taste of this fish, their main predators are humans.


How Do They Reproduce?
Flatheads catfish first spawn at about 4-5 years old. They spawn in June and July, when water temperatures reach 22-23° C (72-75° F). The flathead, normally a loner fish, pairs up with one of the opposite sex and both the male and female construct the nest. They dig out a large hole under a bank or log or dig down through silt and mud until they reach gravel. They spawn in the nest with the female laying eggs in bunches of 30 to 50. A single female can lay 3,000-30,000 eggs depending on her size. When the female is done, she leaves the nest. The male fans the eggs with his fins. After they hatch, he protects the young until they can feed on their own.


Conservation and Management
Flathead catfish are not high on everyone's sport fish list, but they have their dedicated anglers. Besides being attracted to their tasty flesh, many anglers fish for flatheads because of their huge size. Landing a 14-23 kg (30-50 lbs) fish is a rare experience in Minnesota.




Permission is granted for the non-commercial educational or scientific use of the text and images on this Web document. Please credit the author or authors listed below.

Photographs by Konrad P. Schmidt
Text by Nicole Paulson & Jay T. Hatch in cooperation with
the Minnesota Department of Natural Resources' MinnAqua Aquatic Program

This page developed with funds from the
MinnAqua Program (Minnesota Department of Natural Resources, Division of Fisheries)
and the
Sport Fish Restoration Program (Fish and Wildlife Service, US Department of the Interior)

Maintained by Jay T. Hatch
General College and James Ford Bell Museum of Natural History
University of Minnesota, Minneapolis/St. Paul

Last updated 23 October 2002