Climate Change and Shell-Boring Polychaetes (Annelida: Spionidae): Current State of Knowledge and the Need for More Experimental Research.

AbstractAnthropogenic climate change is considered to be one of the greatest threats facing marine biodiversity. The vast majority of experimental work investigating the effects of climate change stressors on marine organisms has focused on calcifying organisms, such as corals and molluscs, where cross-generational phenotypic changes can be easily quantified. Bivalves in particular have been the subject of numerous climate change studies, in part because of their economic value in the aquaculture industry and their important roles as ecosystem engineers. However, there has been little to no work investigating the effects of these stressors on the symbionts associated with these bivalves, specifically, their shell-boring polychaete parasites. This is important to understand because climate change may shift the synergistic relationship between parasite and host based on the individual responses of each. If such a shift favors proliferation of the polychaete, it may very well facilitate extinction of host bivalve populations. In this review I will (i) provide an overview of research completed thus far on the effects of climate change stressors on shell-boring polychaetes, (ii) discuss the technical challenges of studying these parasites in the laboratory, and (iii) propose a standardized framework for carrying out future in vitro and in vivo climate change experiments on shell-boring polychaetes.