Common brittlestar

Ophiothrix fragilis
  • Where it lives:

  • Non native species

About

Brittlestars are related to starfish and have a rounded disc-like body with 5 long, thin flexible arms. They really do live up to their name and will shed parts of their arms if they are disturbed or feel threatened. So look but don't touch!

Common brittlestars are found all around our coasts, in rockpools in the lower shore and offshore to depths of 85m. They live on the seabed and raise their long legs into the water current to filter feed, catching plankton and detritus.

They are often found in dense aggregations where food is plentiful - with numbers of 2000 per square metre recorded.

How to identify

There are several species of brittlestar found in British seas, which can be difficult to tell apart. Common brittlestars vary in colour, from dull brown to purple, red, orange and yellow. Their spiny legs are patterned with coloured bands.

Their fragile arms are often broken off if found in rockpools - a sign of past disturbance or predation.

Did you know?

Brittlestars are often eaten by their larger relatives, the common starfish and the spiny starfish. They hide in cracks and crevices to avoid being eaten, but can also detect a type of chemical produced by their starfish predators and so will move away!

How people can help

When rockpooling, be careful to leave everything as you found it - replace any seaweed you move out of the way, put back any crabs or fish and ensure not to scrape anything off its rocky home.