An exploration of the role of mysids in benthic‐pelagic coupling and biomagnification using a dynamic bioaccumulation model

Abstract A mass‐balance model for the uptake of organic contaminants in the opposum shrimp ( Mysis relicta ) is developed. The model describes the concentration in the mysid as a function of time as it grows and its lipid content changes over a two‐year life span. The model can describe uptake in varying proportions from pelagic and benthic sources. Four mysid scenarios are considered: entirely pelagic, entirely benthic, half‐pelagic and half‐benthic, and following the observed seasonal behavior patterns. The seasonal‐scenario mysid yields results consistent with levels of total polychlorinated biphenyls reported for Lake Ontario (Canada/USA). The relative sediment and water fugacities are shown to play a critical role in determining the contamination level in mysids. Inclusion of mysids in a simple food‐web model demonstrates higher concentrations in upper‐trophic‐level organisms by two effects: introduction of another trophic level in the food web, and increased benthic‐pelagic coupling.