The whelk, or conch, is a member of the phylum Mollusca which also includes the squid and octopus. Unlike those shell-less creatures, the whelk is a ‘gastropod’: it lives inside a single spiral shell which it can retreat into for protection. Gastropod literally means ‘belly foot’ which refers to the fact that its internal organs are covered by a thick muscular tissue or foot which it also uses to drag itself across the sand.