The Pennsylvania Fish and Boat Commission (PFBC) today announced that two independent laboratory tests have confirmed a malignant, or cancerous, tumor on a single smallmouth bass (SMB) caught in the middle Susquehanna River by an angler late last year and provided to the PFBC. The announcement was made during the PFBC’s quarterly business meeting held here today.
Cancerous
growths and tumors on fish are extremely rare in Pennsylvania and
throughout the U.S., but they do occur. This is the only documented case
of this type of tumor being found on SMB in Pennsylvania. The finding
was confirmed by the U.S. Fish and Wildlife Service and the Aquatic
Animal Health Laboratory at Michigan State University.
PFBC
Executive Director John Arway said that although the finding represents
only one individual fish from the overall population, it provides additional evidence that the health of the fish community residing in the river is being compromised.
“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,” he said. “The weight-of-evidence continues to build a case
that we need to take some action on behalf of the fish.”
Since
2005, PFBC biologists have observed more than 22,000 adult SMB as part
of routine surveys in the Susquehanna River basin and have not
documented any fish with obvious signs of tumors. However, PFBC
biologists continue to find sores and lesions on young-of-year bass
during late spring and early summer surveys at alarming rates.
Dr.
Karen Murphy, acting Secretary of the Pennsylvania Department of
Health, said “There is no evidence that carcinomas in fish present any
health hazard to humans. However, people should avoid consuming fish
that have visible signs of sores and lesions."
Arway
added that anglers must make personal decisions on whether or not to
consume fish. He also noted that catch-and-release regulations for SMB
are already in place on 98 miles of the middle portion of the
Susquehanna River where the symptomatic fish was captured and on the
lower 31.7 miles of the Juniata River from Port Royal to the mouth.
The
PFBC first documented disease-related mortality of young-of-year SMB in
the Susquehanna River in 2005. The continued mortality has contributed
to the decline in abundance of SMB. Since 2012, the PFBC has
unsuccessfully petitioned the state Department of Environmental
Protection (DEP) to add the river to the state’s bi-annual list of
impaired waterways.
“The
impairment designation is critical because it starts a timeline for
developing a restoration plan,” said Arway. “We’ve known the river has
been sick since 2005, when we first started seeing lesions on the
smallmouth. Now we have more evidence to further the case for
impairment.”
“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,” he said. “DEP 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.”
PFBC
biologists conduct annual young-of-year and adult SMB surveys on this
stretch of the river from late June through the end of October when
sampling conditions are appropriate. In addition, the PFBC has enlisted
the assistance of certain anglers and guides to provide fish with
obvious masses or lesions if they encounter any when fishing the river.
PFBC
staff are continuing to work with DEP, the U.S. Geological Survey, the
U.S. Fish and Wildlife Service, the U.S. Environmental Protection Agency
and other partners to focus efforts on better understanding what
factors are impacting the SMB inhabiting the middle Susquehanna and
lower Juniata rivers.
PHOTO CAPTION
– Smallmouth bass with confirmed malignant tumor. Caught by angler in
Susquehanna River near Duncannon, Dauphin County, on Nov. 3, 2014. Photo
credit: John Arway
