This dark seashell, reaching up to 2-5 centimetres in length, is called a blue mussel. Both halves of its shell are connected with each other almost without any toothed edges. This mollusc has got threads, which enable it to attach to hard objects. Its favourite places are rocky and stony seabeds.
It likes to swim even up to the depth of 50 metres. It loves salty waters. The blue mussels is a delicacy for flat fish and birds. That is the reason why in the winter, a big blue mussel vanishes from the shallow places in the Baltic Sea, where only its smaller fellows stay.
The blue mussel likes to spend time with other mussels creating a mussel bed, which is a group of friends. They purify the water together, so it can be much clearer. It’s such a good little creature, a real friend of the Baltic Sea!