Cotton spinner

Cotton spinner

Cotton spinner by Coral Smith

Cotton spinner

Scientific name: Holothuria forskali
Although they might not look it, sea cucumbers like this one belong to the Echinoderm group and are therefore closely related to starfish and sea urchins

Species information


Up to 25cm long.

Conservation status


When to see

April - October.


The cotton spinner has short tentacles, unlike other species which have long, feathery tentacles, which means they like to sift through the mud and sand to find food, rather than gathering it from the water column.

How to identify

Cylindrical body up to 25cm long, black on the upper half of the body and yellow on the lower half. Covered all over the top half in black spikes and spines and underside covered in sticky tube feet.


Found off South west and west Britain.

Did you know?

When threatened, this sea cucumber fires out sticky white threads from its rear end!

How people can help

Always follow the Seashore Code when rockpooling, be careful to leave everything as you found it - replace any rocks you turn over, put back any crabs or fish and ensure not to scrape anything off its rocky home. If you want to learn more about our rockpool life, Wildlife Trusts around the UK run rockpool safaris and offer Shoresearch training - teaching you to survey your local rocky shore.