What to Make of the Suquehanna River’s Cancerous Fish

An eagle fishes on the Susquehanna river.
An eagle fishes on the Susquehanna river.Courtesy Pennsylvania Fish and Boat Commission

This week, the Pennsylvania Fish and Boat Commission (PFBC) confirmed that a smallmouth bass caught in the Susquehanna River — once considered world-class fishing waters — had cancer after conducting several tests on a swollen tumor on its mouth. And while cancerous fish are very rare in the country and not hazardous to humans, according to the Department of Health, this particular find still has state officials and ecologists worried for the health of the river. 

RELATED: The 50 Most Adventurous Men

PFBC executive director John Arway said in a statement the discovery is a call to address growing pollution problems in the water: Though it's the first fish to actually receive a cancer diagnosis, the Susquehanna has been what Arway calls "sick" since 2005, when adult bass population numbers began dropping significantly, and later showing sores, lesions, and deformities. PFBC biologists examined more than 20,000 bass in recent years and found lesions cropping up at alarming rates. And in 2014, a U.S. Geologic survey found male bass in the river sprouting female eggs. The disappearance of healthy bass are threatening the state's recreational $3.4 billion recreational fishing industry, while frustrated anglers have weighed in with a long list of complaints on the river's website about strange substances in the water, and a lack of good catches after sitting all day.

We don't know for certain what's causing the diseased Susquehanna bass, but many experts think major pollution in the river is the likely culprit. The river consumes a large amount of sewage waste from plants and nonpoint pollution like runoff from farms — fertilizer, manure, and herbicide. In 2011, environmentalist group American Rivers named the Susquehanna America's Most Endangered River because of fracking around its waters. "Sadly, many of the theories [about pollution] are probably all correct," says David Schindler, PhD, an ecologist at the University of Alberta. Along with high amounts of disease-causing estrogens from human sewage, he says there's a multiple of other industrial chemicals present with endocrine-disrupting properties that could be causing what's seen in the bass. "Such lesions and malformations are seen downstream of the oil sands, and downstream of superfund sites," he says. "They should be regarded as general indices of high industrial, agricultural and human pollution."


RELATED: Can Surfing in Polluted Water Kill You?

Read article

But other experts think more research must be done before linking the cancer to pollution. "One smallmouth bass from the Susquehanna River with a cancer is interesting, but in many ways it is scientifically meaningless [as a single data point]," says Brian Mangan, director of King's College environmental program, who studies the Susquehanna. "We do not know what caused this cancer in this fish." He adds, "while there remains work to be done to help the Susquehanna, people should not fear it or write it off as too polluted to care about."

Like Arway, Schindler thinks what we need for such over-industrialized waters is a new plan that would reduce chemical use. For now, the Department of Environmental Protection hasn't classified the Susquehanna as "impaired" water. That category is used to designate bodies of water too polluted to meet clean water quality standards; if impaired, the government would develop a specific recovery plan that puts the river on a "pollution diet," with more stringent controls on what leaks into the water. In his statement, Arway continued to urge the DEP to "follow the science" and add the Susquehanna to their 2016 list of impaired waterways, which could be the first steps to change.

For access to exclusive gear videos, celebrity interviews, and more, subscribe on YouTube!