This post is just a followup of the one in which I mentioned leafcutter bees, as now I've had the chance to capture a couple of photographs of some.
On occasion you might notice the signs of leafcutter bee activity before you see the bees themselves. This is a picture of some leaves on flowers in our garden, where you can see a few neatly cut-out sections. I'd seen this sort of thing many times before I learned of leafctter bees, and assumed some caterpillar was at work, but I was puzzled as to why it seemed to have eaten in such regular patterns and left, rather than just devouring the whole leaf.
I didn't get a picture of any bees actually harvesting these leaves, so maybe these were done by fickle caterpillars after all, but my money's on the bees.
When I first went outside with camera in hand, hoping to stake out a nesting site where I'd seen a bee the day before, I first crouched down to look around the porch steps to see if I could find the entrance to the nest. Then, I happened to notice that sitting right there on the step was a resting bee, complete with a piece of leaf, almost as if waiting for me to come take her picture.
And as soon as I took this shot, she flew away.
Unlike honeybees, leafcutters are not eusocial; all the females lay their own eggs, rather than tending to the eggs of their mother the queen. According to this site, all leafcutter species are solitary, but alfalfa leafcutter bees (Megachile rotunda) are happy to build nests in close proximity to each other, which is why I think the ones in my backyard are of that species. Each of the drainage holes in the base of these flowerpots is the front door to a leafcutter's burrow; I saw bees come and go from all of them, but they're pretty quick, and it was hard to catch good still photos of any of them. I did manage to catch a little video of some, which I've put on my YouTube channel. Boy, nature photography takes patience!