By my landlord's pool, there is a thin strip of sandy substrate sandwiched between the stone deck of the pool and the steep incline of a raised concrete planter bed. In the later part of May and first few days of June, I observed a growing colony of bees that were building a lovely series of nests in the aforementioned sandy area. I did my best to be patient and get some shots of the bees themselves, but (as you can see) I had limited success -- they were speedy little guys! Sadly, my landlord's instillation of a new sprinkler system in the raised planter bed above the location of these nests seemed to end the colony's development just as it was really beginning to flourish. This series of images shows two bees (they may or may not be the same specimen), as well as images of four different nests (all located within about 10 ft. of one another). While I did not manage to get measurements for the bees, nor all of the nests, I did measure the diameter of the nest entrance holes in this picture to be about 5.5 mm.