Plastic production has continued to grow over the last half century leading to microplastic pollution becoming a ubiquitous pollutant in freshwater ecosystems1. This study investigated the impacts of microplastics on the growth and movement of bluegill-green sunfish hybrids (Lepomis macrochirus x Lepomis cyanellus). Treatments comprised of fish that were fed pellets that were unaltered as a control or contained microplastics derived from either fragments of polyethylene terephthalate bottles, fibers of polyacrylonitrile yarn, or pieces of polyvinylidene chloride film for 30 days. Following exposure, behavioral trials (simulated predator encounters), swim tunnel trials, and respirometry were conducted. While no significant differences in swim tunnel performance or respiration were observed, fish consuming polyacrylonitrile fiber-contaminated pellets exhibited significantly reduced growth. Automated tracking of videos of each trial are currently being analyzed to explore if and how microplastic exposure affected individual fish movement, such as latency of response to an approaching predator, average velocity and the positioning of fish around the arena. Future analyses will investigate microplastic accumulation within the digestive tracts of these fish and effects on the microbiome. These findings highlight the potential for microplastic fibers, among the most abundant microplastics in freshwater environments, to negatively impact fish development and ecological interactions2.