Grubs Up!

I was a volunteer warden at Aden Caravan Park today. Not too stressful.
You really need to look at the extra to get the context of the main photo.
A family of great tits have moved into the hollow barrier and have built a nest. I’m pretty sure they are feeding their young now judging by the number of visits.
I think it’s pretty amazing. Just what lead them to think about building their nest there?
It is certainly secure but unfortunately, it is rather near the ground.
I really hope they all make it.