Red mason bee, Osmia rufa
Red mason bee, Osmia rufa © André Karwath, Creative Commons Attribution-Share Alike 2.5 license
This is a type of solitary bee, although females typically nest in aggregations, giving the impression of a colony. However, each female constructs her own brood cells, using mud, and stocks them with pollen and nectar. She lays a single egg within each cell.
Favourite nesting spots are small gaps and holes in bricks and buildings. But they can also be found in more unusual places like door locks and window frames.
Red mason bees have reddish-brown hair. Both sexes are similar in appearance though females have small 'horns' on their face and males are smaller, lack horns and have noticeably longer antennae.
They are widespread in the UK. Adult bees emerge in April and May, as soon as fruit trees start flowering, and live for about 6 weeks.
Blue mason bees look similar, but are slightly smaller and have a noticeable metallic blue sheen.
