Parasites in the Wadden Sea food web

• Published in: Journal of sea research 2013-09, Vol.82, p.122-133
• Main Authors: Thieltges, David W., Engelsma, Marc Y., Wendling, Carolin C., Wegner, K. Mathias
• Format: Article
• Language: English
• Subjects: amphipod corophium-volutator; Animal and plant ecology; Animal, plant and microbial ecology; Bacteria; Biological and medical sciences; Biomass; Climate change; cockle cerastoderma-edule; Copepoda; east frisian coast; Ecological monitoring; fauna; Food web; food webs; Fundamental and applied biological sciences. Psychology; helminths; Heterogeneity; hosts; Invertebrates; Macroparasites; Marine; mediated indirect interactions; Microparasites; Mollusca; Molluscs; Mortality; Mortality factor; mussel mytilus-edulis; north-sea; oyster crassostrea-gigas; Parasites; parasitism; periwinkle littorina-littorea; population dynamics; predator-prey relationships; predators; Protozoa; Sea food; Sea water ecosystems; seafoods; sylt-romo bight; Synecology; topology; trematode renicola-roscovita; Trophic interactions
• ISSN: 1385-1101; 1873-1414
• DOI: 10.1016/j.seares.2012.06.002

While the free-living fauna of the Wadden Sea has received much interest, little is known on the distribution and effects of parasites in the Wadden Sea food web. However, recent studies on this special type of trophic interaction indicate a high diversity of parasites in the Wadden Sea and suggest a multitude of effects on the hosts. This also includes effects on specific predator–prey relationships and the general structure of the food web. Focussing on molluscs, a major group in the Wadden Sea in terms of biomass and abundance and an important link between primary producers and predators, we review existing studies and exemplify the ecological role of parasites in the Wadden Sea food web. First, we give a brief inventory of parasites occurring in the Wadden Sea, ranging from microparasites (e.g. protozoa, bacteria) to macroparasites (e.g. helminths, parasitic copepods) and discuss the effects of spatial scale on heterogeneities in infection levels. We then demonstrate how parasites can affect host population dynamics by acting as a strong mortality factor, causing mollusc mass mortalities. In addition, we will exemplify how parasites can mediate the interaction strength of predator–prey relationships and affect the topological structure of the Wadden Sea food web as a whole. Finally, we highlight some ongoing changes regarding parasitism in the Wadden Sea in the course of global change (e.g. species introduction, climate change) and identify important future research questions to entangle the role of parasites in the Wadden Sea food web. ► We review the role of parasites in the Wadden Sea food web, focussing on molluscs. ► Parasites can directly affect host population dynamics, e.g. by increasing mortality. ► Parasites can indirectly mediate predator-prey interactions. ► Parasites can also affect the topology and dynamics of the entire food web. ► Global change is likely to affect future parasitism in the Wadden Sea.