sea cucumber edible?

[ballastbelly]

i was watching Bear Grylls, and at minute 14:30 here he is seen eating a sea cucumber:

according to this, the chinese consider it a delicacy, whereas i always keep my hands clear of them, when i am looking under rocks etc as i thought they are poisonous (isnt that why bigger fish dont eat them?)
http://www.vocativ.com/money/the1/the-sea-cucumbers-pickle-in-china/

this link also mentions the mediterranean one
http://scialert.net/fulltext/?doi=ajava.2012.851.859

were these harvested here in the past?  

obviously , dont take the above websites as safe advise, many sea creatures are poisonous
. consult your doctor before attempting to taste any new sea creature