Magpies can cause substantial damage locally to crops such as almonds, cherries, corn, walnuts, melons, grapes, peaches, wheat, figs, and milo. Their damage is probably greatest in areas where insects and wild mast are relatively unavailable.

Magpies pick open wounds and scabs on the backs of livestock. They pick at it until they create a much larger wound which may eventually become infected and, in some instances, kill the animal.

Magpies, like ravens, may peck the eyes out of newborn or sick livestock.