Tumor may be another sign of a sick river
Harrisburg — John Arway was fishing the Susquehanna River last November when his buddy reeled in a smallmouth bass the likes of which neither angler had ever seen.
“It was the grossest fish I’d seen in all the years I’ve fished,” recalled Arway, who is executive director of the Pennsylvania Fish & Boat Commission. “It had this big gelatinous lesion on the side of its jaw. At first, I thought it was a white sucker with a terminal mouth. It didn’t even look like a bass.”
Arway knew something was seriously wrong, so he sent the tumor to a U.S. Fish & Wildlife Service pathologist for testing. When the finding came back as an advanced malignancy, he was stunned, because cancer in fish appears to be rare.
“Cancer has been found in brown bullheads in Presque Isle Bay,” said Arway, who got confirmation of the diagnosis from experts at Michigan State University. “But this is the first documented case of a bass with cancer in Pennsylvania.”
While Michigan State is now attempting to pinpoint the malignancy’s cause, Arway suspects it may be yet another indication of the Susquehanna River’s poor health. “There are several things it could be related to – bacteria… a virus,” he said. “The report from the pathologist is that the most obvious thing is exposure to some environmental contaminant.”
And contaminants abound in the Susquehanna, he said.
Since 2005, the once-stellar smallmouth fishery has experienced a host of problems, including blooms of cladophora algae linked to phosphorous loading from livestock waste, crop and lawn fertilizers, and sewage, and believed to be responsible for periodic die-offs of young smallmouth bass and skin lesions in surviving smallmouths, Arway said.
“The algae are stressing fish and suppressing their immune systems.” In addition, numbers of male bass have been found with eggs in their testes, a condition known as intersex that could be impacting reproduction, according to Vicki Blazer, a biologist with the U.S. Geological Survey.
A range of culprits in addition to agricultural runoff and human waste appear to be causing the Susquehanna’s problems, including pharmaceuticals, and chemical compounds found in everyday items such as toothpaste, plastic bags and hand sanitizers, she said.
“People want one smoking gun, but I think we’re going to find many,” said Blazer. “My gut tells me we’re dealing with a complex mixture of contaminants that are inducing both poor immune response and intersex fish.”
Farms may be packing a double wallop, by loading water with nutrients that feed bacteria and with chemicals used in agricultural production, Blazer said.
“When fish have low immune response, a high phosphorous and nitrogen load opens the door for them to become ill from pathogens that are otherwise fairly innocuous.”
About half of the nation’s rivers and streams are impacted by nutrient overload, said Arway, but some rivers, including the Susquehanna and others in the Chesapeake Bay watershed, have been hit especially hard.
Yet, despite overwhelming evidence of a fishery in deep trouble, the Pennsylvania Department of Environmental Protection has so far refused to declare the Susquehanna as impaired, a status that would open the door to federal funding for water quality improvements, Arway said.
DEP insists it needs to collect more data to make such a determination, although some critics believe push-back from the farm lobby is causing DEP to drag its feet, since a declaration of impairment would force agricultural producers in the Susquehanna River watershed to put their farms on strict pollution “diets.”
Although the EPA has refused to over-rule DEP on the impairment issue, it has agreed, at Arway’s urging, to lead the river’s stakeholders in reaching consensus on the Susquehanna’s by year’s end.
EPA staff will collate data gathered so far on the Susquehanna from various entities, including the Fish & Boat Commission, the Susquehanna River Basin, and DEP, which Arway hopes will result in a determination.
The EPA is already working with Pennsylvania and other states in the Chesapeake Bay watershed on a plan to clean up pollution in the bay. The Susquehanna and its tributaries need the same attention, Arway said.
“The bay is the sum of its parts, and the Susquehanna River is a big part of what feeds the bay. The bay’s pollution starts in the Susquehanna tributaries. We’re got to wake up and do something,” he said.
U.S. Fish and Wildlife Service pathologist John Coll considers the smallmouth malignancy so far an “isolated incident.”