Seashells with a round hole in them?

Question

Sometimes on the beach I find clam shells and sometimes snail shells with a perfectly round hole in them, a few millimeters in diameter. It looks like it was made by some kind of animal. A friend said this is from starfishes. Is that correct?

Answer 1

No, starfishes do feed on mollusks, but they do not drill a hole in the shell. They force the shell open. The holes you describe are made by predatory snails. A hole a few mm in diameter is most likely made by a moon snail, a member of the molluscan family Naticidae. A smaller hole might be made by another snail known as the Oyster Drill. Octopus also make a hole in the shell, but it is very tiny and does not have beveled edges like a hole made by a predatory snail. The snails rasp this hole with their radula, a sort of tooth-covered tongue.

Answer 2

The hole is made by a specific little animal. I learned about it in my aquariumculture class but I cant remember the name. Its not a starfish though. It "drills" a hole in the clam right where the muscle is and eats just a tiny bit of it. This causes the clam to die afterwards.

Answer 3

This hole was made by another mollusc. there is a cirtan snail that lives under water and drills perfictaly round holes up twords the top of the shell. This is not from a starfish starfish open them up.

Answer 4

It's really from drill fish. They bore holes into the shell and suck out the snails.

Answer 5

if you find conch shells with a hole in, that is made by fishermen to get the meat out. it is not perfectly round though