PITTSBURGH (TNS) —Another big fish has been pulled from the waters of Western Pennsylvania, and it may be a state record.

A 34-inch, 18.1-pound walleye caught in the Youghiogheny River on Oct. 28 by Richard Nicholson of Connellsville, Fayette County, is being evaluated by the state Fish and Boat Commission. If the catch is approved as expected, the fish will outweigh the current record of 17 pounds, 9 ounces, caught at Kinzua Dam on the Allegheny River in 1980.

”I was just lucky, that’s all,” Nicholson told the Erie Times-News.

Lucky that he didn’t eat the fish before certification.

Nicholson had a knife in his hand and intended to fillet it and a 9-pounder he’d caught earlier in the same spot to serve at a family fish fry. But his son suggested he wait until they researched the Pennsylvania walleye record.

The Youghiogheny meets the Monongahela River at McKeesport. It was seasonally cool when Nicholson set up on the bank of a favorite 10-foot pool in Connellsvillewhere he had caught 25 walleye over 20 inches this year. His light, sensitive noodle rod —manufactured to provide uniform bend from tip to butt — was strung with 6-pound line and baited with a large live creek chub.

Nicholson’s father, who died in 2015, had shown him the spot 50 years earlier and passed along a valuable tip.

”Big hooks, big bait, big fish,” he said.

At about 7 p.m., an hour after sundown, Nicholson felt the strike, set the hook and — with his rod nearly bent in half — began a 20-minute fight. The walleye thrashed at the river bank and broke the net. Nicholson and his son wrestled it to land. They weighed it there with an old hand-held spring scale and tested it again on a grocery store’s digital scale. The fat fish with 21-inch girth registered 18.14 pounds.

”I knew right then I had the record,” he said.

On the way home, they weighed it again at another store. A Fish and Boat Commission waterways conservation officer checked the weight Monday. For the record to be official, Nicholson has to file paperwork while Fish and Boat confirms the catch was legal.

In Pennsylvania, the minimum size for walleye is 15 inches with a daily limit of six. Nicholson said the Youghiogheny holds larger walleye.

”There’s a lot of good fish in the river,” he said.

Interestingly, the two most recent Pennsylvania walleye records were set on rivers in Western Pennsylvania, not the big waters of Lake Erie. Walleye from the rivers and the Great Lakes are the same species but of different strains. The population has been genetically separated for 14,000 years.

”There are different genetic strains in Lake Erie and the Ohio River [system],” said Tim Wilson, an aquatics biologist for the Pennsylvania Fish and Boat Commission. “It’s actually a very complicated [issue].”

Sander vitreus is native to lakes Superior, Michigan Huron, Erie and Ontario, all that remain of a vast prehistoric glacial lake. Ice Age activity gouged out Conneaut Lakeand reversed the Allegheny River’s original northward flow. When the lake’s ice dam burst, the outflow washed down the Allegheny, which became part of the Ohio Riversystem. Walleye in the Great Lakes and the rivers were permanently separated.

In 2014, a University of Toledo study found that at the genetic level, walleye from the Great Lakes and North American rivers show “considerable genetic divergence and substantial diversity across their range.”

The rift resulted in three genetic strains in separated geographic regions. Great Lakes walleye show the greatest genetic diversity, suggesting the fish intermingled in all parts of the freshwater inland sea. Over the eons, walleye spread from the Allegheny and Ohio rivers into most parts of the Mississippi River system. A smaller genetic strain, the most distantly related to the rest of the population, exists in two West Virginia waterways. The North River flows southwest through the Potomac River to the Atlantic Ocean. The deceptively named New River, actually one of the oldest rivers on earth, flows northward to the Ohio River, ultimately emptying into the Caribbean Sea.

Studies are underway to determine if “resident” walleye that spawn and remain off Lake Erie’s Pennsylvania and New York shores are genetically different from the walleye masses that spawn in shallow western waters off Toledo and migrate throughout the lake.

Research into walleye diversity is new and complicated by widespread stocking in impoundments and rivers before the three strains of the species were known to exist. It is not known how differences in those strains impact the fish, including their length, weight, longevity, spawning success and other characteristics.