Effects of functional traits of fish on their accumulation pattern of microplastics from environment: Evidence from Haizhou Bay

• Microplastics (MPs) were found in all water samples and 93.76 % fish samples from Haizhou Bay. • Inverse Distance Weighting (IDW) revealed more severe MPs pollution in coastal and southern waters in Haizhou Bay. • The generalized linear mixed model (GLMM) results indicated functional traits like trophic level, mouth size and migration type influenced the accumulation of MPs in fish. • Decapterus maruadsi could be used as a biological indicator species for MPs pollution in this area. Microplastics (MPs) pollution poses a threat to marine ecosystems and has been detected in many organisms. Fish serves as a crucial component in the marine ecosystem, several studies have focused on how ecological traits influence the accumulation of MPs in fish. In this study, we evaluated the effects of functional traits of fish on their accumulation pattern of MPs from environment in Haizhou Bay, China. Water and fish samples were collected from 16 sites and subjected to a digestion process. MPs were detected in all 16 water samples and 93.76 % fish samples. The linear regression model indicated that MPs concentration in S. pinguis, C. joyneri, D. maruadsi , and P. argenteu showed a significant positive correlation with the MPs concentration in seawater ( p < 0.05). The generalized linear mixed model revealed that MPs concentration in fish was significantly correlated with their body length, trophic level, migration type and mouth size ( p < 0.05). Fish species with low trophic level and big mouth, inhabiting coastal area, were more likely to accumulate MPs in their bodies. Decapterus maruadsi could be used as a biological indicator species for MPs pollution in this area because of its environmental correlation and eco-economic value. This research reveals the ecological mechanism of MPs accumulation in fish and proposes a new insight in selection of bioindicator for MPs pollution.