Microplastics have been documented in marine environments globally, and because of their small size (1μm to 5000μm) they potentially pose a significant threat to biota. Coastal seas are rich in productivity but also experience high levels of microplastic pollution due to their proximity to human settlements. In these habitats, fish play an important ecological and economic role. This research aims to quantify the microplastic abundance in 252 individuals belonging to six demersal fish species sampled from Galway Bay. Microplastic uptake was observed in 98.8% of all individuals from all species, although, the mean abundance significantly varied between the species. Buglossidium luteum exhibited the greatest mean microplastic abundance per individual, while Callionymus lyra depicted the least i.e. 17 and 5 microplastics respectively. A significant difference was observed between flat fish and other demersal fish. The author hypothesizes that reduced feeding intensity, influenced by seasonality and gut fullness provide probable explanations for the trends observed. Body condition of the fish (i.e. a proxy for fish health) did not correlate with the microplastic abundance. All recovered plastics (i.e. 98% fibers and 2% fragments) were classified as secondary microplastics.
Keywords: coastal region, bio-monitoring, plastic pollution.
