Are sea slugs & sea cucumbers the same?

May 4, 2000
From: Mandy

My 6 year old daughter is doing a report on sea slugs and I was wondering if the sea slug and sea cucumber were the same animal?


Mandy, 2000 (May 4) Are sea slugs & sea cucumbers the same?. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from

Dear Mandy,
Sea Cucumbers are sometimes called Sea Slugs but they are not 'real' Sea Slugs.

If you look above your message, which I have put on the Sea Cucumber Page, there is a photo of a fairly typical sea cucumber, and if you look below your message, at the earlier messages on sea cucumbers, there is quite a bit of information on sea cucumbers.

Basically Sea Cucumbers are Echinoderms, related to Starfish and Sea Urchins. They feed by collecting fine organic particles which form a layer on the sea bottom, with their feathery tentacles which encircle their mouth. In the tropics Sea Cucumbers are collected, the gut removed and the skin dried for food. In this condition they are known as beche de mer, trepang and sometimes seaslugs.

'Real' Sea Slugs on the other hand, are snails that have lost, or are in the process of losing their shells. There are a couple of pages with some general background information on sea slugs [what is a slug?., what is a sea slug?].

Otherwise the whole of the Forum describes, discusses and displays sea slugs. For more general topics go to the blue Navigation Bar at the top and bottom of each page and click on the General Topics button which will take you to a list of general topics. On every page it is worth looking through any messages which are added to the bottom, as they often have more information and photos.

I hope this will help,
Best wishes,
Bill Rudman.

Rudman, W.B, 2000 (May 4). Comment on Are sea slugs & sea cucumbers the same? by Mandy. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from


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