Impact of contamination due to ingestion of microplastics on commercial fish in relation to their trophic habits

Abstract

The abundance of microplastic particles may be linked to fish populations through ingestion, due to the presence of debris throughout the marine environment. In this study, the influence of biological characteristics on the ingestion of microplastics was evaluated in 28 species of fish from the Sciaenidae family and 12 from the Ariidae family in the estuaries of Tumaco and Buenaventura Bay. The samples were collected in high and low precipitation seasons during the years 2020 and 2021, then a characterization of the stomach contents of 894 specimens in Tumaco Bay (479 Sciaenidae and 415 Ariidae) and 758 specimens in Buenaventura Bay was carried out. (267 Sciaenidae and 491 Ariidae) the number of microplastics per stomach was recorded. Additionally, their trophic level (TL) was calculated, and they were grouped into three groups (high, medium, low). As the main result, a positive correlation was found between the trophic level and the consumption of microplastics for both the Ariidae family (p=0.0254) and the Sciaenidae family (p=0.0028). Additionally, differences in consumption were found between TL for the Ariidae family (p(Per)=0.017) and Sciaenidae (p(Per)=0.031), with the high TL being the one that presented the greatest presence of microplastics (MP). This agrees with what was found in studies carried out in estuarine coastal areas, where a positive relationship is shown between the abundance of microplastics and the trophic level of organisms. Likewise, the Condition Factor (CF) presented lower values (<1) in adult individuals that consumed MP, which indicates that the well-being of fish species decreases with this contaminant. These findings indicate that microplastics generate a negative effect on the normal development of fish, as has been reported in other parts of the world.