No, not by a peregrine or even a marauding gull, but a gannet.
On Sunday this gannet decided it wanted to sit well away from the main gannet colony, on a ledge where guillemots were breeding, and there was some understandable threat behaviour going on.
Then the gannet's big flappy feet dislodged a guillemot chick which plummeted off the cliff to its inevitable death - shrieks of horror all round!