The Hole Truth About Flatheads In Rivers Right Now

The season for channel cats on the Minnesota portion of the Red River extends from early May through the end of February. I mention this in an article about flatheads because it's the only legal season for catfish that I'm aware of in North America. Most parts of the country, though, have at least an informal season. Most veteran flathead anglers, for example, begin fishing when water temperatures warm into the low to mid-60F range in spring, and they hang up their rods when water temperatures cool below 50F in fall.

Translating those water temperatures to a calendar can be difficult because weather and water conditions never are constant from one year to the next. During a typical season, though, I'd guess the traditional flathead season in Minnesota extends roughly from mid-May through early October. Heavy cold spring rains might slide the opener back, and a few warm fall days may extend the fishing for a week or two, but northern anglers can expect about six months of fishing during a typical year. Probably add a couple weeks to each end of your season in Missouri and a month or more in South Carolina.

Regardless of where you fish, though, cooling water eventually pushes flatheads into wintering holes that afford them some level of comfort and security. The start of what we call the Coldwater Period is characterized by nearly constant cold water temperatures. Again, how cold depends on geographic location. In the north, some river sections may be covered by three feet of ice, and water temperatures range from a low of 32F to a high of about 39F. Winter temperatures in the mid-South may run in the mid-40F range, and the high 50F range in the deep south.

It follows, then, that a flathead's need for a separate winter range would be strongest in the northern two-thirds of their range. In rivers like the Tallahatchie and Big Black in Mississippi, where water temperatures remain above 50F throughout winter, flatheads may remain in the same areas they occupied during summer. In the Minnesota, St. Croix, Wisconsin, and other northern rivers, though, they usually drop into moderately deep holes when water temperatures dip below about 50F. And so long as these holes aren't filled in by changing river dynamics, fish may inhabit the same wintering holes from one year to the next.

Studies on the Minnesota River conducted by biologists with the Minnesota Department of Natural Resources found that channel cats and flatheads favor different wintering holes, though some overlap occurs. While channel cats tend to congregate in the deepest available water, flatheads favor holes with heavy wood cover or rock structure that blocks current, usually in water 12 to 18 feet deep. Most fish in the Minnesota River don't move far, but a long migration may occur in some rivers.

It has long been assumed that these wintering flatheads--especially those at the northern edge of their range--seldom bite, though they're occasionally caught by anglers fishing with jigs or bait for walleyes or some other species. A reliable pattern has been difficult to establish, though, because most of these anglers weren't targeting flatheads, and most of the fish they reported catching were snagged.

In recent seasons, though, we've met anglers like John Lehto and Terry Hansen who do indeed target flatheads in northern rivers during the coldest times of the year. Both are coldwater catmen to the core. Neither pursues flatheads during the traditional summer season, but both routinely break through ice at the boat ramp thick enough to support an ice fisherman, and they brave temperatures cold enough to send ice fishermen in search of a propane heater.