Haylee Crawford and Sam McArthur of Balclutha Primary School asks :-
Why is an Octopus slimy and how do they make the slime?
Jean Mckinnon, a marine biologist at Otago University responded.
Octopus are slimy for several reasons and some octopus are slimier than others! The main reason an octopus makes slime is to protect it's skin. An octopus skin is very delicate and can get hurt very easily by being scraped on rocks or sand. Even sea anemones can sting an Octopus so badly that it gets blisters. The slime helps prevent this. Some types of octopus spend their days buried in sand, they use slime to cover themselves so that sand can't get into their gills and they can still draw water in and out. The Southern Sand Octopus buried itself deeply in sand and uses the slime like cement to make a little cave and a burrow. The Octopus can hide in the cave and pump water in and out through the burrow.
Relatives of the Octopus, the Bottletail Squid can produce slime. They use this for defence. The slime is only produced when the animal is disturbed or attacked. A Bottletail Squid can produce twenty times it's own body size in slime very quickly. Although we don't know what the chemicals are in the slime, it is likely that they either taste bad or are poisonous.
Octopus and the Bottletail Squids make the slime in special glands on their bodies, usually on the underside or amongst the arms. Slime is also known as mucous and is formed by adding water to very long molecules of protein. A very small quantity of the protein can make very large quantities of slime. If you want to know more about Octopus and their cousins check out http://www.tonmo.com.