Physiological Effects of Microplastic Ingestion on Yellow Perch (P. flavescens)

Laura Matthews

Matthews MicroplasticsLaura poses with a Yellow Perch specimen

Recent studies have revealed that microplastics (plastic particles <0.5mm in size) contribute considerably to plastic pollution in aquatic ecosystems; however, their direct effects on fish health require more research. My project aims to study how yellow perch—a freshwater fish with sport and commercial value—is physiologically affected by microplastic ingestion. The primary objectives of this study are to determine the effects of microplastic ingestion on the growth and condition of juvenile yellow perch and examine how microplastics move through their digestive systems.

This was accomplished by holding and observing yellow perch fed a diet of resynthesized food pellets (either with or without microplastics) for 5 weeks. Three treatment group were used, with two serving as controls for mass and nutrients while the experimental group included microplastics. In nature, if microplastics are replacing portions of fish diet and then remaining in their stomachs for an undetermined amount of time, fish may feel full and eat less; thus, the two mass treatment groups served as controls for food volume and nutrition.  Furthermore, respiration rates of the fish were tested as an indicator of metabolism. Fish were humanely euthanized at the end of the study period and will be dissected to examine their stomach contents and determine how much plastic has accumulated in their digestive systems.

Data is still being processed, but differences between treatment groups would suggest negative health effects from the microplastics. Thus, the results of this study could be used to identify potential health hazards of microplastic pollution on a fish common to our Great Lakes. This information could be used in support of efforts to reduce such pollution and clean our freshwater systems.