Integrating abundance and diet data to improve inferences of food web dynamics

1. Both population abundances and chemical tracers are useful tools for studying consumer-resource interactions. Food web models parameterized with abundances are often used to understand how interactions structure communities and to inform management decisions of complex ecological systems. Unfortunately, collecting abundance data to parameterize these models is often expensive and time-consuming. Another approach is to use chemical tracers to estimate the proportional diets of consumers by relating the tracers in their tissues to those found in their food sources. Although tracer data are often inexpensive to collect relative to abundances, diet proportions provide little information on the per-capita consumption rates of consumers. Here, we show how integrating these data sources can be used to better estimate of consumption rates. 2. Our modeling approach informs traditional multispecies population abundance models using proportional diet data. We used simulations to determine wheth...