The flathead catfish is Minnesota's largest native catfish. Commercial anglers have reported netting flathead catfish as large as 100 pounds, and as recently as 2017 a flathead catfish in the 70- to 80-pound range was voluntarily released by an angler fishing in the St. Croix River near Stillwater. If you have never fished for flathead catfish now is a good time to try it.
- When to fish
The inland fishing season opens in early April and closes in late November. The opening and closing dates vary for lakes and rivers that border North Dakota, South Dakota, Canada, Iowa and Wisconsin.
Check the fishing regulations based on where you want to fish. Some waters have special regulations for flathead catfish.
- Inland: waters within Minnesota
- Border: waters that border other states or countries
- Special: waters listed by name that have special or experimental regulations in place that differ from statewide regulations.
Flathead catfish fishing tends to be best in summer. During winter flatheads seek deeper water where boulders or logs provide refuge from current. There they remain through the winter, so torpid that they may be covered with a fine dusting of silt.
Times of lower light conditions – dusk and dawn – are good times to fish. So are rainy and overcast days as flatheads prefer low light conditions and spend most daylight hours in the shade of a tree or rock or other type of cover.
- Where to fish
Minnesota's flathead catfish live in the southern part of the state, largely in the Mississippi River below the Coon Rapids dam, the St. Croix River below Taylors Falls and the Minnesota River.
A good place to start on the St. Croix River is near the town of Stillwater. Fifteen-pound flatheads are relatively common in this area. Similarly, Pool 2 of the Mississippi River – that portion between the dams at St. Paul and Hastings – is a good bet.
In the southwest, flatheads exist only below the Minnesota River Granite Falls dam. July and August are perhaps the best months to fish for trophy flatheads because they have just completed spawning. A great place to catch one- to two-pound eating-sized channel catfish is upstream of Montevideo.
Good fishing often exists where you find submerged timber, especially rootwads. Catfish like to be in areas where the water is relatively deep compared to the rest of the area and baitfish are plentiful. If this area has only moderate or low current that is even better.
The flathead feeds primarily on other fish using its sense of smell and ability to detect vibrations through its lateral line. At night it may more actively feed or even forage in shallow riffles.
- How to fish
A common catfish rig is a sturdy rod-and-reel loaded with heavy line of at least 30-pound test or more. On rare occasions a flathead will grab an artificial lure but usually they are caught on large live baitfish or gobs of nightcrawlers lowered into deep pools or heavy cover. Flatheads usually shun the dead baits and “stink baits” that are popular for channel catfish.
Flatheads can be caught from either a boat or shore. Fishing with a group of friends for catfish on the shore of a river is a great way to spend an evening.
- Gear
Many catfish anglers prefer rods in the seven feet long or slightly longer. Basically, you want a rod that can cast your bait a good distance and is sensitive enough to detect a light bite but strong enough to wrestle a good-sized fish. Similarly, many catfish anglers prefer bait-casting reels over spin-casting reels but either will work.
- What's important to know
- Catfish don’t sting but they can give you a painful poke if you are not careful. That’s because they have sharp spines. One spine is on the top of the fish. Two others are located on the side of the fish, one on each pectoral fin. So, when handling a catfish grasp the fish firmly behind the dorsal (top) fin and place your thumb on one side behind the pectoral fin and your index finger behind the fin on the opposite side.
- Catfish will drop your bait if they feel too much resistance. So, fish with as little weight as necessary to keep your bait on or near the bottom.
- Basic biology
- The flathead looks different than other catfish. It has a squared tail rather than a forked tail. It has a long body and wide flattened head with beedy eyes. The lower jaw protrudes beyond the upper jaw.
- The flathead’s color varies with its environment but is generally mottled with varying shades of brown and yellow on the sides, tapering to a lighter mottling on the belly.
- The flathead catfish spawns in summer when the water reaches 72 to 75 degrees.
- The flathead nests in cavities such as hollow logs, rootwads or log jams in quiet water.
- After spawning the male drives the female off the nest and then guards the eggs until they hatch.
- The state record channel catfish weighed 70 pounds.