How satellite avoid birds in space?

Satellites without propulsion are sitting ducks—they simply get hit.

Satellites with propulsion are in better shape, the International Space Station being a prime example. The Joint Space Operations Center (JSpOC) tracks debris. There are several programs that can be used to provide warning of close approaches so the satellites can be maneuvered to of the area of high collision probability. Unfortunately, many pieces of debris are too small to be detect yet too big for a collision to be survivable.