As temperatures rise here in the Bay Area (we are the lucky ones in most of the U.S.), bees are beginning to sense that the time has come to emerge. Spring brings several species of mining bees (Anthophora spp.) that have been overwintering in their underground burrows. California is home to roughly 60 species of Anthophora, of which 6 are commonly found in our urban survey work. Females are medium-sized with robust pollen-collecting hairs on their hind legs. Some species, like A. californica and A. urbana have striped abdomens, whereas others like A. edwardsii and A. pacifica have mostly dark abdomens without banding. Males, two pictured above, often have pale colored markings on the front of their faces, though it’s hard to tell as they zoom by in a grey blur.
Some species congregate in areas and group their nests in large aggregations. In the wild, nesting aggregations of A. edwardsii can sometimes contain hundreds of individuals! You might notice it when you see dozens of male bees hovering just over the ground waiting for a virgin female to emerge from her nest. The males then pounce on her in a fight to be her suitor and tussles often occur where large balls of bees roll around until a winner is declared.
These bees are generalist foragers but some of their favorite blooms include the Pride of Maderia, lavender, catnip, salvias, and coreopsis. Be sure to have some early blooming plants in your garden for these spring flyers.