Exploring the effects of consumer-resource dynamics on contaminant bioaccumulation by aquatic herbivores

We explore the consequences of consumer-resource interactions for bioaccumulation in two aquatic systems (cadmium accumulation in Dreissena polymorpha and polychlorinated biphenyl accumulation in calanoid copepods). We explicitly link the feeding and growth rates of consumers to the abundance of resources under a variety of assumptions about the nature of the interactions between them. The models are parameterized using field and laboratory data, and predictions are quantitatively compared with field- measured distributions of tissue concentrations. Different assumptions about consumer-resource interactions result in different predicted distributions of tissue concentrations and illustrate the way these interactions constrain the bioaccumulation of contaminants. Linking feeding and growth rates to resource abundances will be important whenever these abundances change over time. User-friendly software will make these ideas accessible to nontheoreticians.