The availability and ingestion of microplastics by an intertidal fish is dependent on urban proximity

Abstract

ABSTRACT Investigating the impacts of the plastics on our environment, and the potential adverse effects on fauna, has become increasingly important. While a number of studies have shown that microplastic levels in sediments generally increase with proximity to urban regions, fewer studies have investigated how vertebrate ingestion rates vary with urban proximity. Here we explore how urban proximity influences plastic abundance in sediments and plastic ingestion by an intertidal fish (Forsterygion capito). Three sites around Dunedin City, New Zealand, were sampled. We demonstrate that fish collected from areas located 2.5 and 10 km from the city centre ingested significantly more microplastic than fish at the furthest site, 25 km away from the city. Likewise, we found that the sediments from the least urban site tended to contain fewer microplastics. Despite this, we found little evidence to suggest that sediment microplastics can predict microplastic ingestion. Overall, this research provides further support that urban proximity impacts microplastic deposition and ingestion by marine fauna.