Biomagnification of mercury through lake trout (Salvelinus namaycush) food webs of lakes with different physical, chemical and biological characteristics

► Mercury biomagnifies through aquatic food webs to toxic levels in top predator fishes. ► Among-system differences in mercury transfer through food webs occur but have not been explained. ► Diverse lakes supporting lake trout were compared to understand the ecosystem processes that affect mercury biomagnification. ► Higher biomagnification of mercury was found in larger, higher nutrient lakes. ► Results show that the food web processing of mercury is related to ecosystem properties.