i use wd-40 and it worksd for a while. they will keep trying until they have rubbed it off. I bought one of those feeders that pulls down when the weight of the squirel gets on the feeded, then they cant get to the food opening. The ended up chewing the plastic so a hole opened adn all the feed fell to the ground.
We have a metal feeder with the spring to hold it open unless too much weight is applied (birds can eat but squirrels close the door) but the squirrels will hang upside down from the roof to get to the seed. They will get the baby birds from the birdhouses too. The only real solution seems to be the .177 one.
