do they need oyster shells?

Quote:The chickens know when they need extra calcium and will eat the oyster shell when they need it. So, it's a good idea to provide it to them free-choice. I have a little container (a parakeet feeder, to be specific) attached to the inside wall of my coop near the pop door for them to eat as they see fit.

You can feed their own egg shells back to them but you should boil them and crush them finely first. For my money, it's easier and cheap enough to buy the oyster shell.