A FLYING squirrel? Wow! I've never seen one! If it were me, and you have other bluebird houses, I'd probably let it do its thing, just to see what would happen and for the novelty of it.

Mom would probably feel differently :) She's not a huge squirrel fan. I think she would say to remove the nest.

I think our bluebird house is too close to our house, and they didn't move in. :( They checked it out a lot, but I haven't seen them in a while.

peanut butter on the outside of the house & pest repellant on the holder thing for it (so no bugs get to PB). I really don't remember where I heard this from, but I don't think squirrels like PB...lol. Of course, I could be completely wrong...

I'm with Connie. Flying squrrials are nocternal, usually. My dad discovered them in his nut trees years ago when he was fighting a war with grey squrrials over the pecans. He wired the tree and the next morning found two dead flying squrrials. Extension agent identified them for us - we were sad. Needles to say the critters got the nuts that year. the agent told us they are actually very prolific in TN but due to night activity and small size are rarely seen. by the way, our squrrials like peanut butter, I feed it to blue birds in winter and they eat it too if they get to the feeder.

Just put up a no fly zone sign by the bird house. Blue birds can't read.

SQUIRREL!!! Lol...reminds me of one of our favorite family movies, Up. =)

I'd probably leave them alone this year because I have a soft heart for little fuzzy critters, but I would consider one of those plastic bird house opening guards next year to keep the squirrels out then. Many gardeners kill squirrels, but I don't think I could ever get myself to do that.

Squirrels LOVE peanut butter, and in fact some squirrel poisons use peanut butter as an attractant.

Maybe that's what I heard...use PB with poison.

Could you just relocate the bird house till they are done with it?