MEPS prepress abstract   -  DOI: https://doi.org/10.3354/meps14638

ABSTRACT: Parasites play many regulating roles in ecosystems that are increasingly recognized. In coastal ecosystems, the trematode Himasthla elongata infects blue mussels Mytilus edulis, a foundation species that shapes the functioning of intertidal communities. Although the largest impacts of infections are during the summer months, the parasite forms long-lived cysts in the mussels that can be harmful to their hosts under winter conditions. Here, we experimentally show that even moderate infection levels by H. elongata have a detrimental effect on the survival and growth rate of wintering blue mussels. These parasite-induced costs during winter may potentially affect the populations of blue mussels in coastal habitats, with ramifications for the whole ecosystem.