Birds of prey that have fed upon the carcasses of the infected. Beady eyes, sharp claws, sharp beaks, and very much crazy. That shrill cry should send a tingle up anyone's spine.
Always found in a small flock, these birds can cause a lot of damage in a little amount of time. They seek to overhwhelm their prey by attacking in their large numbers, and peck them to death. A flock of crows were responsible for the death of S.T.A.R.S. member Forrest Speyer in Resident Evil 1. Crows are usually more of an annoyance than a formidable enemy, as long as you don't allow yourself to be cornered by a large number of them.
Most of the time that you will find them in the game however it takes something to spook them before they attack so be careful with what you do when you hear or see them around. You might just trigger an attack.