I'm sorry Mr Nuthatch, but I don't think there's much point in looking in there.
Firstly, it's spoken for and even more important, you can't get in - the hole's too small!
But what's this at Box2?
That doesn't seem to put this nuthatch off - after all, he wants to check it out for himself.
It's in a nice place isn't it? ...
... and you're a lovely looking bird that we'd love to have to stay!
Perhaps another year we'll make the hole bigger like the other nest box! We'd love to have a nuthatch occupying one of our boxes!