Predators
Predation of blue mussels is greatest during the 3 weeks it spends as a planktonic larva. During this stage it is susceptible to jellyfish and fish larvae through adults. Once the mussel metamorphoses the mussel is still restricted by predation, however only smaller mussels with thinner, weaker shells are victim. Once the shells becomes stronger, blue mussels are preyed upon by sea stars such as Asterias vulgaris as well as by several species of sea gulls. Small mussels are also eaten by the dog whelk, Nucella lapillus. The blue mussel is host to a wide range of parasites, but these parasites usually do not cause much damage.
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