I did read somewhere that wasps will bite the heads off already dead bees and take the thoraxes back to their nest for the young to feed on - but I don't think that could apply in this instance because it looks like the bodies have been discarded after decapitation, almost as if they were of no use
Dave I'd say a hornet has raided a bumble bee nest for the grubs, decapitating all the bees that attacked it in the process.... but where you are in NI there are no hornets are there? So must be a wasp as Annie suggested. In the "Life in the Undergrowth" series there was footage of 6 or 7 japanese hornets raiding a honey bees nest and decapitating literally 1000s of honey bees in just a few minutes, to get to the grubs and honey.
Yeah, you could be right about hornets there. There are hornets here, I have only seen a few before, non e reciently, but will keep a lookout. Thanks for ideas guys
I Googled 'headless bees' and one of the first headings that came up was this:
JSTOR: The Baltimore Oriole and Carpenter-Bee- [ Traduire cette page ]It was only under these trees that the headless bees were found, but there they lay in hundreds; the ground was literally speckled with them. ...
links.jstor.org/sici?sici=0003-0147(187212)6%3A12%3C721%3ATBOAC%3E2.0.CO%3B2-Z - Pages similaires - À noter
Unfortunately when I clicked on the page it told me I didn't have the right to access the document. But clearly someone has already investigated this phenomenon...