Mark Mosby of St. Anthony caught one big fish when he went to the St. Croix River near Stillwater with his fishing buddy Aug. 2.

The flathead catfish set a state record in the catch-and-release length category, the Minnesota Department of Natural Resources (DNR) said.

The fish measured 52½ inches long with a girth of 32 inches. Although weight is not required for the catch-and-release record, the fish was estimated to weigh between 70 and 80 pounds.

Mosby, who described himself to the DNR as an occasional angler, said his buddy made sure his fishing gear was ready for battle as they were targeting big flathead catfish known to inhabit that stretch of the St. Croix.

"Kudos to my fishing partner John Kaiser for his knot-tying ability," Mosby said. "The flathead put up a great 15-minute fight right up until he got to the boat and the knots held true."

Mosby's fish was caught on 80-pound line with a 40-pound monofilament leader.

There are two kinds of state records in Minnesota: one for catching and keeping the biggest fish in each species based on certified weight, the other for the length of a caught-and-released muskellunge, lake sturgeon or flathead catfish.

According to Wikipedia, the flathead can grow to a length of 61 inches and can weigh up to 123 pounds, making it the second-largest North American catfish, after the blue catfish. The average length is 25 to 46 inches. The maximum recorded life span is 24 years.

Jake Robinson of Shakopee previously held the state record for flathead catfish with a 49-inch fish caught May 15 in the Minnesota River near Savage. That fish had a 33½-inch girth and was caught on 100-pound test line.

The DNR recommends that anglers become familiar with the record-fish guidelines and be ready to take the required photos and go through the correct procedures for submitting a record.