I was blaming Squirrels

Last year in early spring my wife bought a bird feeder. One morning I looked out and the feeder was on the ground and all the bird feed gone. I had seen a squirrel so I blamed it the squirrel. Well I put the feeder back on the tree branch. One night I heard something and turned on the light. The feeder was on the ground and two raccoons were eating the spilled food. So I got one of these:





Two nights later I got one of the raccoons. Took it deep in the woods and let it go. The next night I got the other one and did the same with it. I thought good problem solved. Boy was I wrong. 29 raccoons later I finally think the problem is over. Raccoons are usually night animals but we would sometimes see them after the food in the day time. Any of you have any problems with raccoons?