Transfer of Microplastic Debris From Mussels to Prey Fish in the Great Lakes
- Funded By: Notre Dame Environmental Change Initiative
- ECI Investigators: Whitney Conard, Katherine O’Reilly, Gary Lamberti
Microplastics are emerging pollutants in the Great Lakes, the world’s largest freshwater system. Recent evidence suggests that contaminants, including bacteria and persistent organic pollutants (POPs) such as PCBs and dioxins, may accumulate on the surface of microplastics and be passed on to sport fish and ultimately humans. While most microplastics research has focused on the marine environment, relatively little work has focused on microplastics ingestion by freshwater organisms.
As dreissenid mussels are now ubiquitous throughout the Great Lakes, they represent a source of contaminants that round gobies can transfer to higher trophic levels. This potential ability of gobies to vertically transmit contaminants to piscivorous sport fish represents a novel pathway of bioaccumulation and cycling, and thus, their continued spread and population increase will likely have major ecosystem consequences. Furthermore, the current decline in alewife and pelagic energy pathways in general may increase the significance of round goby to higher trophic levels. Increased mobility of contaminants such as heavy metals, POPs, and microplastics may ultimately lead to poor fish condition and human consumption risk.
Using asian clam and mottled sculpin as surrogates for dreissenid mussels and round gobies, this research works to inform Great Lakes managers, researchers, and decision-makers of the potential for microplastics to bioaccumulate up the food web. This pilot study at ND-LEEF serves as the starting point for further research into determining how dreissenid mussels and round goby contribute to microplastics transfer to higher trophic levels in natural aquatic systems.