Mussels are amongst the most copper sensitive marine species. However this sensitivity may depend on the environment (e.g. salinity, dissolved organic matter in the seawater), their age (larvae or adult) or the population mussels come from. With the exception of organic matter, the European copper risk assessment does not take these variables into account and therefore mussels may be over- or under protected against copper toxicity.

Overprotection may increase economic costs associated with reduced copper emissions and under protection results in declining aquaculture gains and ecological losses (lower biodiversity, reduced water filtration,.). Mussel populations from the Baltic Sea live in brackish water, vastly different from the rest of Europe's seas. Several studies have already indicated that their body functions are altered to survive in this brackish water. However, a slower growth rate compared to mussels elsewhere in Europe indicates that they do not live under optimal conditions. At the moment there is little information if mussels that live in these suboptimal areas are more or less sensitive to copper compared to other European mussel populations. Therefore it is unknown if additional actions or regulations are desirable to protect these mussel populations.

The goal of the project is to determine the copper sensitivity of a Baltic Sea mussel population near Askö and to evaluate the influence of changing environmental parameters (e.g. salinity) on this copper sensitivity. Previously this work was done for a North Sea population (Middelkerke, Belgium) and an Adriatic Sea population (Venice, Italy). Adding the results obtained from a Baltic population to this dataset can improve the current European copper risk assessment.

Researcher

David Deruytter, Applied ecology and environmental biology
section: Laboratory for environmental toxicology and aquatic ecology, Ghent University