Blue Tit Quandary

[Tuppeny]

Hi, I am new to WAB and joined in the hope that someone might be able to give me some sound advice! We have some Blue Tits nesting at the bottom of old water pump (handle still attached). The nest seems to be situated about a foot below the water spout - idea to protect them from preditors but our fear is that in a few weeks they won't be able to get out, is there anything we can do to assist their survival when the time comes for them to take their first flight?