Captain Nolan Koepp and David Grisar started fishing out of Green Bay, Wisconsin at 6:30 a.m. on October 7 and they would go on to break the state’s record for longest muskie. They launched Koepp’s 21-foot Ranger boat into the Fox River, motored into the Bay, and started trolling multiple lures from stout rods.
They’d caught nothing by late morning, and Koepp knew a strong west wind was forecast as the sun rose.
“I ran from the southeast shore of the bay to the west side so we could fish in the leeward part of the bay,” Koepp tells Outdoor Life. “It was a little bumpy, but good for trolling there.”
Koepp, from Two Rivers, Wis., is a 19-year charter captain on Green Bay, and David Grisar, of Saukville, is his dentist. The two have fished and hunted together, but never for muskies. Grisar had never caught a muskie, and he knew Green Bay was prime water for big muskies. Koepp is a top muskie guide on the bay.
“We hadn’t been trolling long – it was just after noon,” Koepp, age 38, says. “We were trolling in 7 feet of water, and suddenly a fish slammed one of the lures – a 6-inch-long ‘Blue Water’ muskie diving crankbait in perch color.”
Grisar grabbed the bucking rod while Koepp cleared the other trolling rods from their holders.
“He fought the fish for about 10 minutes on an Okuma trolling outfit with 50-pound braided line, and an 80-pound fluorocarbon leader,” Koepp says. “The fish never jumped, but it sure fought hard and deep.”
Grisar got the big fish close and was stunned at its size. Koepp told his dentist-angler that the fish was huge, likely the biggest he’d ever seen.
Koepp netted the massive muskie, brought it aboard his Ranger and quickly measured it on a bump board.
“I’ve had some 55-inch muskies come aboard before, and some heavier, but never one that length – 57.5 inches,” the experienced Green Bay guide says. “I didn’t get a measured girth on the fish, but I’d estimate it to be about 25 inches around. I think it weighed about 40 pounds.”
Koepp unhooked the fish, measured it, took a few photos and released it in just two minutes, he says. He wanted to be sure to get the prized muskie back in the water as quickly as possible for sure survival.
“The fish was in great shape and swam away strong,” he says. “Green Bay muskies are feeding up hard for the coming winter. They’re gorging on shad and perch, and will soon start moving into feeder rivers.”
Grisar submitted photos of his muskie’s length to Wisconsin’s Department of Natural Resources fisheries officials, who have certified his catch as a new Badger State record catch-and-release muskie.
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Grisar’s fish tops the previous catch-and-release muskie measuring 57 inches, caught by Illinois angler Sam Becker in August 2025. Three catch-and-release muskie records were set in Wisconsin in 2025 – all from Green Bay.
With Grisar’s fish, that makes four consecutive state muskie records for Green Bay.
Koepp says Grisar will have a replica mount made of his record muskie.
“I still have the Blue Water plug that he used to catch his fish, and it’s got some large muskie teeth holes in it,” says Koepp with a chuckle. “If he wants it, I’ll sure give him the lure. It would look pretty good hanging in that mounted muskie’s mouth.”