Growing as large as five feet and over 100 pounds, flathead catfish are one of North America’s largest fresh water fish. Their preferred habitats are deep pools, lakes, and large slow-moving rivers. Within these waters they prefer submerged cover such as logs. Good flathead spots typically include structure, located in relatively deep water ideally with moderate current, and access baitfish. Flatheads typically prey only on live fish.
As their name suggests, they have flat heads, yet they looks similar to other catfish. They come equipped with a smooth, scaleless skin, barbels, and spines on the dorsal and pectoral fins. Flathead are typically yellowish to light brown on the back and sides, with a yellowish to cream belly.
Reaching sexual maturity in three to six year, spawning occurs from late May through August, when the water temperatures reach 75 degrees or better. Flatheads prefer to nest in areas with submerged logs and other debris. Females lay approximately a 1,000 eggs per pound of body mass. After four to six days, the eggs hatch and the fry school together at the nest for several days, where the males guard them aggressively.
Flathead Catfish in Texas
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, sharp 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.
Unlike other catfish which are scavengers, flatheads prey only on live fish. Young flathead catfish feed mostly on invertebrates such as worms, insects and crayfish. When 10 inches or larger, their diet consists entirely of fish-shad, carp, suckers, sunfish, largemouth bass and other catfish (including their own kind). Flathead catfish are eaten by alligators, water snakes, turtles, larger fish, and humans. They reach sexual maturity between the third and sixth year. Spawning season is from late May through August, when the water temperature is between 75° and 80° F.
Males select hollow logs, caves or areas beneath the banks for their nest sites. Males may even improve their selected sites by creating shallow depressions for the females to lay their eggs. Egg number varies greatly depending on female size, but the average is up to 100,000 eggs at a time. Scientists estimate that a female will lay 1200 eggs for every pound she weighs. A female flathead that weights 50 pounds might release 60,000 eggs at a time. After an incubation period of four to six days, the fry (very young fish) will school together at the nest for several days after hatching; afterwards they will seek shelter beneath rocks, roots and other cover and begin their independent lives. Average lifespan of the flathead catfish is 12 to 14 years, but one recorded flathead catfish lived 24 years.
Adults are usually solitary, each staking out a favorite spot under a tree or in a cove, in deep water. At night, they move into shallow areas to feed. Males defend their nest and eggs aggressively. They will fan the nest with their tails to keep the eggs clean and provide them with oxygenated water. If females have been eating poorly, their bodies may conserve resources by not releasing eggs. Poor overall health and certain environmental conditions such as drought or flood can reduce flatheads' ability to spawn. In healthy times, clutches can reach 100,000 eggs, but only a small number will survive.
Flathead catfish prefer deep pools of streams, rivers, canals, lakes and reservoirs, where the water is turbid (cloudy) and the currents are slow.
In size, flatheads are the second largest sport fish in Texas after their cousin, the blue catfish. Among those who selectively fish for catfish, flatheads fall just behind channel catfish as a prized species. Where mature populations exist, 50-pounders are not unusual. Typically, the largest fish are caught by trotliners, who have landed specimens in excess of 110 pounds. Rod and reel anglers may have the greatest success with flathead catfish just below reservoir dams. "Catfish" is the second most preferred group of fish among licensed Texas anglers, and flatheads rank second behind channel catfish. Because of their popularity with anglers, they have been introduced in many other states where they have adapted well. In some cases, however, they have out-competed the native fish species, causing those native fish populations to decline sharply, disrupting some natural ecological processes.
Catfish have long, sharp spines on the front edges of their dorsal fins that are connected to venomous glands. Although the spines can tear skin, the glands excrete venom. The venom is irritating and some people have had serious problems with infection afterward. (If you are "stung" by a catfish and are worried about it, please call your doctor.).
Courtesy of Texas Parks and Game