This was taken during the summer at the Fletcher Wildlife Garden. A number of bee boxes had been placed around the garden by an Agriculture Canada bee scientist, attracting a lot of bees who nest in holes (cavities). The holes are quite small, and were lined with rolled tubes of paper to make examining the nests easier. I stopped and looked at the boxes frequently and one day saw this tiny bee with a peculiar green 'thing' on its back. It is probably a pollen pack but in an unusual place. Later, I saw a honey bee (Apis mellifera) also with a pollen pack on its back. I don't really know why this occurs and have not been able to find out more (yet).