DIVE IN
MUSSELS
The delicious shellfish are also water quality indicators.
By Susanne Masters
Illustration by Alice Goodridge
On late autumn days a cold water comfort is taking advantage of clear water for swimming down to check out mussels (Mytillus edulis). As seawater cools plankton growth slows. The saying about only eating shellfish when there is an ‘r’ in the month is a reflection of how at warmer temperatures harmful algal blooms are more likely. Mussels are filter feeders and they concentrate toxins in their flesh, which can reach levels that are toxic to people who eat them.