I have had my bird feeders up since last winter. When it is cold, that is the hardest time for birds to find food; and they are so happy to flock around the feeder and eat the seeds there.
At first, the squirrels were just coming along and taking all of the bird's food; so my husband got some PVC plastic pipe, and made a little sleeve over the part of the hanger that sticks out. Now, when the squirrel tries to climb out on the hanger to get to the feeder, it spins and tumbles him off. After a few days of trying to figure it out, the squirrel now leaves the feeder alone, and just rummages around the ground underneath for any seeds that the birds drop.
We put the second feeder up on the side of the house, so there is not way for the squirrels to get close to that one, and it is great to be in the kitchen and see the birds flying up to get their food.
We have wrens, and some cardinals, and there are mourning doves that pick up the seed off of the ground.
