Help What has happened!! (1 Viewer)

I have been monitoring my first ever bird box and have had a family of blue tits come and go over the last 3 weeks. Now all of a sudden there is no activity, opening up the box i found that the nest is full of maggots and there is obvious signs of small chicks. Can some one suggest what might have gone wrong?.

Photo attached (but it is not very nice!!)
Thanks, Chris

Maybe the parents were predated by a cat or raptor and the chicks starved, it happens.


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