Mark Mosby of St. Anthony Park, MN caught a big fish near Stillwater on August 2. A really big fish.

The 52-1/2 inch flathead catfish set a new record for catch-and-release in the state of Minnesota, and also beat Wisconsin’s catch-and-release record.

It was 32 inches around and estimated to weigh 70 to 80 pounds.

Mosby caught the fish on an 80-pound line with a 40-pound monofilament leader.

“Kudos to my fishing partner John Kaiser for his knot-tying ability,” he told the Department of Natural Resources. “The flathead put up a great 15 minute fight right up until he got to the boat, and the knots held true.”

The fish was about three inches longer than the previous record-holder, caught in the Minnesota River in June. It was five inches longer than the first catch-and-release record holder, which was also caught in the St. Croix last May.

Flathead catfish differ from other catfish because they only hunt and eat live prey, consuming sunfish, crayfish, and other aquatic animals. They prefer to live in large river pools with logs and other debris on the bottom to provide cover. The fish is native to the watershed, but is a nuisance in other parts of the country where it has been introduced by humans.

The DNR created new catch-and-release categories last year because many anglers no longer wish to kill trophy fish. Anglers can continue to set records based on certified weight, which require the fish to be harvested. Guidelines and application forms for each type of record are available on the record fish page.

The all-time record catfish in Minnesota, which was harvested and weighed in at 70 lbs., was caught in the St. Croix in 1970.

Wisconsin’s record flathead catfish was caught in the Mississippi River, and was 53 inches (just half an inch longer than Mosby’s fish). The state’s catch-and-release record for the species is 40 inches.

Other record-setting fish species from the St. Croix watershed include:

• American Eel – 6 lbs, 9 oz; 42″ – Near Stillwater, 1997
• Longnose Gar – 16 lbs, 12 oz; 53″ – Near Prescott, WI, 1982
• Northern Hogsucker – 1 lb, 15 oz; 14.25″ – Sunrise River, 1982
• River Redhorse – 12 lbs, 10 oz; 28″ – Kettle River, 2005
• Lake Sturgeon – 94 lbs, 70″ – Kettle River, 1994
• Slimy Sculpin – 0.8 oz., 4.75″ – Kinnickinnic River, 2016