Odd Situation

I have had a female Great Tit roosting in a new bird house (with camera) about 4.5 metres high in a tree. Been there since November last year. Returns every night and would nestle up to the camera and benefit from the heat. It was not there last night. This morning I noticed a deceased newt at the bottom (male juvenile). No wafter dark and not return tonight. Anyone care to venture a hypothesis as to a likley explanation. Hole saize 32mm.