Swimmers and snorkelers are not likely to find them on purpose or by accident in shallower intertidal waters. Their shells become prized items when found empty on sandy beaches. Shells range in size from less than an inch up to 9 inches long. The organism unwinds itself in the shell to come out of the opening. A sharp stinger stabs prey with venom much like a harpoon.
Cone snails hunt worms and other snails.
A few eat fish, and these varieties are most harmful to humans. Avoid contact with these animals. The animal's harpoon can penetrate even gloves. The toxin is similar to the paralytic toxin of the Pufferfish and Blue-ringed Octopus . Symptoms can begin within minutes or take days to appear.