Effect of anemone presence on blue mussel Mytilus edulis predation by the sea star Asterias rubens

The effect of anemone attachment on the predation of the blue mussel Mytilus edulis by the common sea star Asterias rubens was tested. These organisms are found in abundance around the island of Sylt, where their interactions shape community structures. Overall, a preference for mussels without anemones over anemone-equipped mussels and preference for mussels covered with other epibionts over epibiont-free mussels were observed. This indicates that A. rubens do not simply avoid anemone-equipped mussels due to physical hindrance but rather that the avoidance behaviour is specific to anemones, possibly due to their ability to deploy cnidocytes for defence.