Did you know?
They're generally between 5 and 40 cm in diameter and feed mainly on plankton.
These jellyfish can form massive blooms in the water, which may be so dense that it becomes difficult for small boats to travel through.
They're found in both inshore seas and oceans and can withstand temperatures as low as -6 and as high as 31 degrees Celsius.
They are Britain's most common jellyfish, but can have massive populations in some areas, but be totally absent from others. It's been found up estuaries and in harbours and is especially common in Scottish sea lochs. They swim by pulsing the main umbrella shaped part of their anatomy, but swim to stay at the surface of the water rather than travel through it. It means the tentacles can be spread over the largest possible area to catch food better.
Experience life in the cool seas and see creatures from our coastal waters as well as deep-water dwellers