Fish Cancer Confirmed for First Time in Pennsylvania River

The Pennsylvania Fish and Boat Commission just released its findings.

Smallmouth bass with confirmed malignant tumor. Caught by angler in Susquehanna River near Duncannon, Dauphin County, on Nov. 3, 2014. Photo credit: John Arway.

Smallmouth bass with confirmed malignant tumor. Caught by angler in Susquehanna River near Duncannon, Dauphin County, on Nov. 3, 2014. Photo credit: John Arway.

The grotesque image seen here is not a movie still from some awful Sharknado spinoff. It is a photograph of a smallmouth bass caught by a fisherman in the Susquehanna River, and the Pennsylvania Fish and Boat Commission (PFBC) has confirmed that the growth on the fish is a cancerous tumor. It’s the first time a smallmouth bass has been documented with a cancerous tumor in the state. It’s also the first documented instance of fish cancer among all species in the Susquehanna River.

The fish was caught in 2014 and turned over to the PFBC for testing. Two independent lab tests confirmed the fish cancer, and the results were confirmed by both the U.S. Fish and Wildlife Service and a research laboratory at Michigan State University.




According to a statement released by the PFBC, fish cancer is extremely rare in the state and throughout the country, but it's not unheard of.

"As we continue to study the river, we find young-of-year and now adult bass with sores, lesions and more recently a cancerous tumor, all of which continue to negatively impact population levels and recreational fishing," PFBC executive director John Arway said in the statement, adding that while it's only one case of fish cancer in the river, it doesn't bode well for the overall health of the river. "The weight-of-evidence continues to build a case that we need to take some action on behalf of the fish."

Over the last decade, scientists at the PFBC have examined more than 20,000 smallmouth bass from the Susquehanna River, finding sores and lesions at what the PFBC calls "alarming rates."

So, what if you catch a fish with a big old sore or lesion on it? Do we really even need to answer that?

"There is no evidence that carcinomas in fish present any health hazard to humans," an official from the Pennsylvania Department of Health said. "However, people should avoid consuming fish that have visible signs of sores and lesions."

Ya think?

“If we do not act to address the water quality issues in the Susquehanna River, Pennsylvania risks losing what is left of what was once considered a world-class smallmouth bass fishery,” Arway said. “[The Pennsylvania Department of Environmental Protection] is expected to release its 2016 list of impaired waters in late fall. We are urging them once again to follow the science and add the Susquehanna River to the list.”

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