Abstract
Food webs are a complex array of trophic interactions. With a heavy emphasis on "classic" predator-prey interactions, most studies of trophic dynamics completely omitted parasitic interactions. However, recent work has shown that parasites contribute significantly to many aspects of trophic structure. In the current study, I have estimated the biomass transfer by parasites and predators from members of the genus Stegastes from multiple sites in the Caribbean. These results show that most of the parasite-driven biomass transfer comes from ectoparasitic gnathiid isopods. Moreover, I have found that predation rates are high for juveniles and decrease as they become adults, while the opposite is true for parasitism. Despite this, more biomass is being transferred from adults than younger stages via both predation and parasitism. I also show that in coral reef ecosystems, parasitism can transfer more biomass than predation for adult Stegastes. These results highlight the contribution of parasites to energy flow in coral reef environments and suggest that they must be considered in future food web studies.