Intersite variations of a battery of biomarkers at different levels of biological organisation in the estuarine endobenthic worm Nereis diversicolor (Polychaeta, Nereididae)

► The present paper is based on the recognized need of considering stress effects at different levels of biological organisation. ► This strategy has been developed in estuarine areas, crucial for the ecological and economic health of coastal regions. ► Biochemical, physiological, behavioural biomarkers and population effects were examined over more than one year in the ragworm Nereis diversicolor, a sentinel species important for the structure and functioning of mudflat ecosystems.