Shroggs landfill - another querie !

Yesterday I came across  14 dead bees on a short (50m) stretch of woodland footpath. The bees were more or less intact except that their abdomens had been cleared out to look like empty eggshells.

This morning I checked the path again to find another 11 dead bees with the same condition.

I can't work out what has happened to them to be be dead in such a short area of fairly open woodland. It left me with a few questions.

Was it that cold easterly wind that affected them and they took shelter ?

But then why were the abdomens cleared out so cleanly - and by what ?

Perhaps a bird but I suspect birds would have demolished the bees completely. Maybe a parasite another insect or maybe even a small mammal. More questions than answer's for me. 

They looked all like the same species of bee but I'm not much on identifying them !

Any ideas ?

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