I love ‘Mason bees’ because they return to my wildlife garden every year. Their name stems from the fact that they will excavate holes in sandy mortar between bricks. Each year I watch them hovering around the walls of my home looking for any holes between the bricks which they can exploit. Last year I decided to give them a helping hand by drilling a few holes in the walls to encourage them to lay their eggs in them. A mason bee only lays one egg in each hole but I’m not sure how many eggs they lay each year. That could be something for you to look into. Please let me know when you find out.
I thought this could be a chance to make a video, so I kept a keen eye on my holes, and soon enough I notice a mason bee going in and out of one of them. This is what happens: First the bee puts in some pollen, then it lays just one egg which oval in shape. Then it puts lots more pollen into the hole which will be food for the larva when it hatches. Finally it seals the hole wit lots of mud. This all happens in a day or so then the bee leaves, never to return. The larva soon hatches but it will not leave the hole until the next summer. I’ll be putting the video up soon so please call back to see it (Nov 2013)