A smallmouth bass with a tumor on its lip was confirmed in Pennsylvania, according to the state's Fish and Boat Commission.
It said the fish was caught last year in the Susquehanna River and tested positive for cancer.
The commission called the finding rare, but local fisherman said they aren't surprised.
Jacob Myers and his family have been fishing on the river for decades.
He's even joked about the abnormalities in the fish he's caught.
"You know, we're just waiting to catch one with three eyes," he said.
Though the bass caught in November may look surprising to some, to anglers, it's normal.
"If you go up to Sunbury where Juniata lets in, you can just see there's a big clean mark into the Susquehanna where the Juniata lets in and then it's all muddy,” Myers explained. “It's pretty bad but it's what we've got to fish."
Pollution in the river has been an issue before.
Two years ago, the commission sought to have the waterway declared impaired.
However, the Department of Environmental Protection did not agree.
It said there's not a clear distinction between whether there's a water quality issue or if it's a bass problem.
Either way, people told reporters that they would never eat a fish from the river. For them, it's just catch and release.
"I feel that it's unsafe,” said Aleem Harden, a fisherman “If we were to catch a fish you would see the spots and stuff that are already on the bass. It's just that right there is enough for me. I wouldn't dare."
The Fish and Boat Commission said it is still urging the DEP to add the Susquehanna to its list of impaired waters.
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