HARRISBURG– A multi-agency, multi-year study names the most likely reasons there are fewer smallmouth bass in the Susquehanna River.
The Pennsylvania Department of Environmental Protection (DEP) and the Pennsylvania Fish and Boat Commission (PFBC), along with nearly 50 participants and 6 partner agencies have determined hormone-disrupting compounds and herbicides as well as pathogens and parasites have caused the smallmouth population to decline.
Tumors and lesions found on smallmouth bass along with a population crash in 2005, sparked the team into action, using ground-breaking monitoring strategies to collect more than 30,000 water quality records annually.
The Susquehanna River is one of the most complex river systems in Pennsylvania, making the study a difficult task. “What looks like just one body of water acts like five unique rivers, all with different characteristics,” said John Quigley, DEP Secretary.
The original potential causes included high flows, pH and dissolved oxygen (deemed unlikely as a result of this study), as well as invasive species, habitat, and algal blooms (deemed uncertain).
The team says more research is needed, but the next step is to focus on identifying the sources of the herbicides and other dangerous compounds.
“This study does not identify a single smoking gun,” said Quigley “But it does point the way toward likely causes, which we will continue to pursue. On top of that, through this study, DEP staff developed new approaches to monitoring this complex system, dramatically increasing our water quality monitoring capacity in the Susquehanna River, and providing tools that we can use to ensure fishable, drinkable water statewide.”
The full report can be found here.
