You and I might reach for a claw hammer, but all this mason bee needs are his own legs--his very strong legs. Watch him pull the long nail completely out of the hole.
What's happening here? The bee is probably returning home. The Daily Mail quotes zoologist Lynn Dicks:
Dr Lynn Dicks a research fellow from Cambridge University's Department of Zoology explained the bee's behaviour: 'Mason bees like this usually choose existing holes rather than excavating their own.
'I have never seen anything like this and suspect that the nail was places in a nest hole this bee had already started using. This would explain its urgency to remove the nail - it may have laid eggs or have larvae inside.'