|One of the
commonest solitary bees, Osmia bicornis (formerly Osmia rufa), is more commonly known as the Red Mason Bee.
Both sexes are densely clothed with reddish brown hairs, with the male
having a dense tuft of white hairs on the front of the head, with the
female's head being entirely dark brown/black.
It has an
annual life-cycle and is active in spring and early
summer, from late March through to the end of June. The
adult's life span is relatively short, the female making
small nests of a few cells within simple holes in walls
and wood. The cavity is filled with a supply of pollen
and then closed up. The larvae then develop and pupate,
but don't emerge until the following Spring.