The size and strength of flathead catfish have inspired tales both tall and true. Expanding populations have spawned a new generation of freshwater big-game anglers.
I never saw a flathead catfish until I was 31 years old. Talk about miss-spent youth. Then I moved to south Georgia to conduct fishery research on the rivers and reservoirs of the coastal plain . . . and to learn to fish for the king of the North American catfish.
Flatheads were introduced to that part of the world, reportedly around 1950 when commercial fishermen, eager for quarry larger than the native channel cats, white cats, and bullheads, brought a load of adults from the Tennessee River drainage in Alabama and dumped them into the upper Flint River. By 1970, they became the dominant predator in that section of the Flint and gradually spread downriver, passing three dams to enter the Apalachicola River in Florida.
Such stories of flathead expansion have been repeated from the Atlantic Coast to California, where the species has spread through the lower Colorado River and the Imperial Valley. Elsewhere in Georgia, the flathead’s invasion of the Altamaha River has caused an uproar among the region’s redbreast anglers who fear, with reason, that flatties will chow down the prime sunfish.
The Department of Natural Resources has responded with a low-level eradication program, including sponsoring harvest tournaments and removing fish by electrofishing, then donating them to food shelves. Meanwhile, in North Carolina, invading flatheads in the Cape Fear River now are being taken by commercial fishermen armed with low-voltage electrofishing rigs.
The Cape Fear population began with the stocking of 10 adult fish. Let’s leave discussion of the wisdom and outlook of fish removal programs for another time. The point is that these range extensions illustrate the adaptability and dominance of this species.
Flatheads Across North America
The native range of flathead catfish includes the larger rivers of the Mississippi, Missouri, Ohio, and Rio Grande river basins from the Great Lakes south into northern Mexico. Flatheads thrive in rivers that range from tributaries just 100 feet wide to the lower reaches of the nation’s largest rivers. Although rightly called a warmwater fish, flatheads also can survive and grow large in cool waters. In 1978, the first flathead ever caught in Canada was taken in a commercial trap net on the Ontario side of Lake Erie. And the Minnesota state record stands at 70 pounds, larger than the Georgia record.
Slower, warmer rivers of the central and southern regions seem most conducive, however, to growing large numbers of big flatheads. Until 1992, the International Game Fish Association (IGFA) and National Fresh Water Fishing Hall of Fame recognized a 98-pounder caught in 1986 at Lewisville Reservoir, Texas, as the all-tackle rod-and-reel record. They disqualified this fish, however, because it was accidentally snagged with a jigging spoon.
This leaves a 911⁄4-pounder caught in 1982 from the same body of water as the record. Kentucky lists a 97-pounder, caught in the Green River in 1956, as their state record. Texas lists a 122-pounder from the North Fork of Buffalo Creek as their trotline record.
Fish of this size are approaching those that anglers on every big river swear live in deep holes below the dam. Belief in outsize catfish usually is based on observations by teams of divers sent to inspect these aging structures. Many of the divers have sworn off dam duty after these experiences, preferring to work on oil rigs set in the shark-infested Gulf of Mexico.
Flathead catfish inspire tales both tall and true, as they rank among the largest North American freshwater fish, and their slightly monstrous appearance (to the uninitiated) makes them formidable gamefish. A 30-pound fish is beyond the realm of experience for nearly all freshwater anglers. So when one breaks a bassman’s line, its estimated size increases in direct proportion to the diameter of his eyeballs when the fish spools him.
Most rivers in the flathead’s original range have been dammed, creating large impoundments that provide good habitat. Gizzard and threadfin shad abound, providing prey for all sizes of cats. Sunfish species, bullheads, and skipjack herring add to the smorgasbord.
These species also occur in rivers, plus many species of large suckers that slide smoothly down a flathead’s gullet. But while studying the diet of flatheads in the Flint River, I was surprised to find even big fish scarfing young-of-the-year shad less than an inch long. They’d upchuck this partially digested shad soup in the livewell.
The big flatties must have cruised through the schools with their mouths open like a pod of baleen whales. Flatheads in this limestone-based river also consumed lots of crayfish, the most common prey for fish less than about 10 pounds.
Not surprisingly, flatheads grow fast, generally faster in terms of weight than any predatory fish on the continent, exceeded in some systems only by the common carp and grass carp. Their fastest growth spurt typically occurs between ages 3 and 8 when they add several pounds a year. But even big fish grow fast, with tag returns indicating increases of more than 10 pounds per year, in some cases. Record-size flatheads haven’t been aged, to my knowledge, though they certainly can live at least 20 years.
In reservoirs, flatheads find spawning holes in undercut banks or rocky ledges in feeder creeks, along riprap banks, and in hollow logs lying on the bottom. Like channel cats, male flatheads clean or excavate a burrow and lure a female to lay her clutch of eggs. He then drives her out and tenaciously defends the lair for weeks as eggs hatch and small cats grow to an inch or so, when they venture forth.
In most reservoirs around the United States, flathead populations are thriving, providing anglers with overlooked opportunities to catch the fish of a lifetime. In some areas, commercial fishermen have increased operations, lured by the high value placed on flathead flesh by anyone who likes to eat fish. And the trophy status of this fish has spawned a new generation of freshwater big-game anglers.
Flatheads have been experimentally stocked in ponds, but with their aggressive nature and large appetite, they initially grow fast, cropping off all available prey, then stagnating. No, the flathead is a fish of big water, though within that big water, it may use only a small piece of turf during a season.
Seasons of the Flathead
As a proper warmwater fish, flatheads retire in winter to deep holes where current can’t tumble their slumbering bulk. According to divers and biologists who have sampled catfish in winter, hordes of big fish clump into prime spots, sometimes mixing with big channel cats. Silt may cover these fish, and divers can prod them with little reaction.
In large river systems, flatheads move downstream or out of small tributaries to pass the winter in big deep holes that provide a stable environment. In smaller rivers, the deepest holes in a long stretch of river suffice, and these spots may gather bass, sauger, walleyes, and other species.
Warming spring conditions draw flatheads from the winter doldrums toward shallow areas where they resume feeding. In reservoirs and smaller impoundments, that movement often brings flatheads into smaller creek arms where warming water also lures sunfish, shad, carp, crappies, bass, and nearly everything else—all potential prey for a big cat.
Flatheads hold in creek channels, though maximum depth may be only 8 or 10 feet, balancing their bulky heads against stumps until the approach of a preyfish puts them on alert. Flatheads are nocturnal feeders, with the largest fish seemingly least inclined to feed in daylight. But in spring, more than at any other time of year, big fish are more active during the day, perhaps because sunlight concentrates prey or warming water boosts the cat’s metabolism, bringing on a feeding urge.
In rivers, flatheads move upstream to feeder creeks, backwaters, or bays. As waters warm through the 60°F range and into the 70s, flatheads feed heavily, often bringing the best bite of the year. Flatheads spawn at water temperatures in the low 70°F range at the northern extent of their distribution, like Minnesota. This typically occurs in July or even early August in the north.
In Georgia waters, water temperature may be in the mid-80°F range before the spawn starts, as early as late May, or into June in most cases. The period of nest preparation and defense brings a slow-down in catfish action as fish disperse to spawning holes and don’t roam to feed. But just as with bass or other species, not all spawning occurs at once in large complex systems. Cooler, deeper sections of rivers or reservoirs sustain the good prespawn bite.
Late summer brings a resumption of feeding, with fish in reservoirs and big rivers more scattered than during the Prespawn Period. Action in small rivers centers around deep holes with heavy cover, a more predictable location than in other systems.
In reservoirs, flatheads nocturnally roam large flats that provide cover and shad. Trotliners score well with their shotgun approach—set lines on 10 good flats and most will have a fish or two, maybe a bonanza on one. Anglers must be more selective in location due to the inherent inefficiency of their gear. No shortcuts or magic locational formulas exist. Experience on the water teaches you more each year.
Flatheads feed until water drops into the low 50°F range, when most catmen hang up their gear. This may be a mistake in some situations, as breakthroughs by blue catfish anglers like Jim Moyer demonstrate blues catchable in water below 50°F. Still, flatheads are the most warmwater dependent of the big cats.
Cooling water gradually draws flatheads from smaller, shallower sections of small rivers toward deep wintering holes. Fish in tributary rivers often migrate to deeper wintering grounds in the larger river fed by the tributary. Timing of this shift seems to vary among systems, but it certainly is underway when rivers fall below 60°F. We know only a little about patterning flathead catfish in fall.
Big baits and big fish in thick cover call for heavy tackle. No surprise that most of the biggest cats ever caught were taken without rod and reel. Heavy braids and squidding line used on trotlines and jugs hold the biggest fish, especially when they’re linked to a shock-absorbing section of truck tire tube.
To land a big flathead from a river on less than 20-pound-test line seems more a matter of luck than skill, unless you hook one on the channelized portion of the Missouri River or other canal-like stream. But you almost never find big ones there, anyway. For most situations and average-size flatheads, a 61⁄2- to 7-foot muskie rod and 25-pound test does fine. You will break off, however, if the holes you fish have fallen trees, timber, or sharp rock ledges.
Doug Stange is a student of cat rods, having experimented with countless blanks for channels, blues, and flatheads. “In theory and in practice,” he says, “the best rod for an intense battle in close quarters is a heavy-power, medium-fast-action fiberglass rod about 51⁄2 feet long. Such a stick provides more leverage with less torque, and thus less strain on the angler.
“Longer rods cast farther and fish baits better at long distance. And, of course, they protect lighter line from breaking. On a short rod, a big flathead can break 40-pound test in a second if you don’t get him turned.”
Clicker mechanisms on big baitcasters like the Ambassadeur 6500 and 7000 or Penn 209 hold line and signal bites. Medium retrieve ratios give cranking power, and the sturdy construction stands the abuse of flathead catfish and those who pursue them.
For bankfishing tailraces and large impoundments, long heavy-duty surf rods built on spinning blanks fill the bill, for they’re designed for similar duty in coastal waters. Longer surf rods launch heavy baits farther, though shorter stiffer blanks can put more pressure on fish. A 9- to 11-foot model can launch half a gizzard shad and four ounces of lead to the other side of the river, where a dark eddy beckons.
Depending on the areas you fish, you may need a couple heavy baitcasting and long spinning rods to handle all situations. Flathead catfish aren’t shy of line or other gear. Eighty-pound-test line, an 8/0 hook, and six ounces of lead mean nothing if a lively fish is attached. Abrasion-resistant monofilament line is the choice of most flathead fanciers, though some catmen prefer braided dacron for its lack of stretch, which provides no nonsense hooksets at long range and can turn a fish before it wraps around a stump.
Choose sinkers according to depth, current, and bait size. Two- to three-ounce bell and egg sinkers predominate, with bell sinkers getting the nod in rivers because they hold better. In fast tailraces, 4 to 10 ounces may be needed.
When fishing in current with baits likely to spin—medium gizard shad, small bluegills, and pond-raised suckers are notorious for this—rig a heavy barrel swivel between the hook and sinker. The swivel also keeps the sinker separated from the bait, usually 3 to 12 inches. Strong basic bait hooks like the Eagle Claw 84 and Mustad 92671, 3/0 to 10/0 depending on bait size, work fine for flatheads.
A flathead’s first run is the most powerful so if it heads for a stumpy lair, put on the brakes or say bye-bye. Careful, though, because a cat that seems tired has plenty of energy for another charge, to break line at boatside, or to rip out of your grasp. About grasping—do so only with heavy gloves for protection unless your paws are as calloused as a lumberjack’s. The inside edge of the teeth on a cat’s lower jaw cuts as the cat violently shakes its head.
Releasing catfish is, in some locales, a novel or even alien practice. At In-Fisherman, we’ve long suggested the policy of selective harvest for all fish species—keeping smaller fish of any tasty species for meals, while carefully releasing rarer or more vulnerable portions of the population.
Flathead catfish grow fast and are abundant in many waters. Keeping small and medium-size (10 to 20 pound) specimens from such waters is a great way to enjoy the renewable resource with a great meal for family and friends.
In small streams, though, the number of larger flatheads probably is limited, for fish over 20 pounds may be 10 years old or more. The same’s true of 30-pounders in medium-size rivers. Releasing most larger fish in these systems helps keep the population strong, with enough big breeders to reproduce and to tear up someone’s tackle next year.
Taken from Elk City Reservoir, Kansas, on May 14, 1998, the fish stretched the tape a whopping 61 inches and sported a pleasantly plump, 42¾-inch girth. Paulie was crappie fishing at the time, and hooked it on a jig-and-minnow. Like many world records, it was not without controversy. It was verified while alive by Kansas Department of Wildlife and Parks fishery biologist Sean Lynott. But details of the catch—such as the relatively light tackle Paulie was using, and his statement that it didn’t put up much of a fight—raised eyebrows in the cat community. Still, the record stands to this day as a testament to the immense proportions flatheads are capable of attaining.