Someone with a BB gun is maiming sea gulls in the Manhattan Beach and Playa del Rey areas.
Three gulls were wounded and two others were maimed.
The Humane Society of the United States is offering a $2,500 reward for information leading to the capture of the shooter.
The birds had multiple BB pellet wounds.
Rachael Newman of the International Bird Rescue and Research Center, which treated the gulls, says one bird had two BBs in its wings and another in its beak. It is still recovering.
Two other birds found wounded in Manhattan Beach had their wings shattered by BBs, and they were euthanized.
Two other gulls found in Playa del Rey with broken and maimed left wings were also euthanized.