It is a year round battle to keep the squirrels from eating the bird food.  We bought “squirrel buster” feeders which we fill with sunflower seeds and that works well.  The peanut feeders (for the Tits and the Woodpeckers) are not as well designed and we usually have to repair them every few weeks with wire and heavy duty tape.  It’s a game of war and the squirrel is not likely to win.