Blue mussels (Mytilus edulis) are ecologically important ecosystem engineers, yet populations in some coastal habitats appear to be declining. At the same time, artificial structures such as floating pontoons and jetties, which can be favourable habitats for epibiota like blue mussels, are becoming increasingly common along developed coastlines.
This work explores how different natural and artificial habitats influence blue mussels along the Swedish west coast, investigating variation in their abundance, morphology, genetics, survival, growth, and recruitment. Findings so far reveal that abundance is similarly high on rocky shores and floating pontoons, but very low on soft sediment bottoms and jetties.
We also find significant differences in shell morphology between these habitats, in addition to mussel farms, suggesting strong plastic effects or possibly local adaptation. Reciprocal transplant experiments show that mussel survival and growth is significantly higher on pontoons than intertidal shores, and that the habitat mussels originate may also play a role in their performance and survival.
Together, this work highlights the importance of artificial habitats for blue mussel populations and explores implications for the management of coastal urbanisation and the future of blue mussels in Sweden and beyond.
