bird of ill omen

a little bird told me

I received the information from a source which I am not prepared to disclose.

be taken ill

To become ill.

bird in the bosom

A secret pledge that one makes for another.

bird of one's own brain

One's own idea or conception.

do ill

To harm, to injure.

early bird

A person who wakes early or arrives early, typically before most others.

flip the bird

To make a rude or obscene gesture (at somebody); particularly, to extend the middle finger.

ghetto bird

A police helicopter, specifically in the context of patrolling or searching impoverished, high-crime urban areas (the ghetto).