
Microplastics in White Sucker (Catostomus commersonii) and Common Carp (Cyprinus carpio) from the Upper Thames River, Ontario.
Abstract
Microplastics (plastic particles < 5 mm) are abundant in aquatic environments, particularly near urban areas. Little is known, however, about how variation in microplastic abundances within watersheds affects fishes. Microplastics were examined in demersal fishes—white sucker (Catostomus commersonii) and common carp (Cyprinus carpio)—across 11 sites in the Thames River, Ontario. Microplastics were found in 44% of white sucker, ranging from 0-14 particles per fish, and 31% of common carp, ranging from 0-128 particles per fish. Across both species, the number of microplastics in fish was higher in urban sites than rural sites, and there was a positive relationship between the number of microplastics in the fish and the abundance of microplastics in the sediment. Body mass was also positively related to number of microplastics in fish. Together these results provide insight into environmental and biological factors that may be influencing the variation of microplastic ingestion in demersal river fishes.