It must be pretty tough being a blue tit. Yesterday there was a magpie sitting on the roof. Today a starling tried to get in through the front door. The blue tit youngsters must still be in there (I saw an adult with food) and presumably the starling can hear them chirping inside. If the image below is going to be typical then leaving home for the blue tits is going to be a dramatic business.
I don’t know if starlings predate blue tit youngsters but I’ve no reason to assume they don’t. The starlings have been keeping an eye and a claw on the nestbox all day. I wonder how this one will play out …