When summer's dog days arrive, walleyes go dormant, bass get lockjaw and pike's teeth fall out!

Of course those are old wives' tales, yet there's no doubt that hot-weather fishing can get tough. However, with water temperatures at their warmest, our most unsung Minnesota game fish -- catfish -- reach peak activity levels.

If you've tangled with a bruiser flathead or a sleek channel catfish, you know the thrill. If you haven't had the pleasure, then it's time to turn this summer's dog days into cat days. All it takes is a little understanding of our state's catfish resources, and some insight from top catfish guides on where and how to fish for them.

MINNESOTA'S CATFISH
Minnesota is home to both flathead and channel cats; we're too far north for blue catfish. While closely related, flatheads and channels differ in many ways that will affect your approach when fishing for each species.

Flatheads are Minnesota's largest catfish, with specimens of 40 and 50 pounds caught each summer. A 20- or 30-pounder is great, and many 5- to 10-pounders are caught as well. These hungry predators eat suckers, bullheads, bluegills, redhorse, river chubs and any other live creatures they can fit into their gaping mouths. Flatheads live undercover in deep holes, but come out at night to hunt in shallow riffles, sandbars and flats where baitfish abound.

Channel catfish typically run smaller than flatheads, but are extremely sporty. Fifteen- to 20-pounders are caught each summer, but 2- and 3-pounders are normal and make good eating. A 5-pounder is big in most waters, a 10-pounder exceptional. Like flatheads, channel catfish prefer woody cover, but channels are more likely to feed during the day. Channels are partial to scavenging, so they're OK with smelly food, but they also eat various live prey from fish to frogs.

Three river drainages offer Minnesota's best catfishing. All those waters are within a few hours' drive of every angler in the state. In the northwest, the Red River of the North offers one of the country's finest channel catfisheries, right in our own back yard. The Minnesota River is prime flathead water, with channel catfish as well. And the St. Croix River is a channel catfish haven, with plenty of monster flatheads mixed in.

RED RIVER OF THE NORTH
"The Red River of the North is a superb fishery," says Brad Durick (www.redrivercatfish.com, 701-739-5808), a catfish guide whose clients slime up his boat with hundreds of big channel catfish weighing more than 20 pounds each summer. "The whole Red River is awesome," he says. "You can't go wrong fishing anywhere, but the fish get bigger from south to north." The river flows northward.

"I like the stretch from south of Fargo through Grand Forks," says the accomplished guide. "You can work the whole gamut of summer catfish spots in this stretch -- faster current areas and seams, snags, holes and flats. Fish these places and you will eventually run into cats. Farther north, the river gets wider and shallower. Here it's all about current breaks and holes. There aren't many snags.

"Fargo has three beautiful landings to get on the river," Durick points out. "There is a nice new landing at Halstead too, and there's good fishing up and down from there. Oslo (18 miles north of Fargo) has a good new landing as well. That's a good spot to put in and fish."

One essential tool for the Red River fisherman is a Red River of the North Canoe and Boating Guide, available at the Minnesota Department of Natural Resources Web site, www.dnr.state.mn.us. This three-part map shows all the river's boat access points, shore fishing spots such as parks, and more.