About twenty percent of all bee species in North America don’t bother to collect pollen. It’s not that they don’t need pollen for raising their young, because they do. But they would rather steal it than do all that hard work.
We always think of bees as being the ultimate pollinators, so that one-in-five number is sobering. These so-called cuckoo bees don’t even have the hairy bodies we usually associate with bees. In fact, they look like more like wasps.
So how do they manage to raise their families? Easy. They just hang around a nest that is under construction. When the female bee—often an Andrena—goes out for another load of pollen, the cuckoo bee darts in, lays an egg on the pollen provision, and “gets the hell out of Dodge.” That’s it: motherhood is convenient, quick, and clean. No mess, no fuss, no toiling all day over a hot flower.
Last week I took a short stroll to my favorite springtime bee place in the Mima Mounds Natural Area, a big patch of kinnikinnick in the middle of the prairie. Within ten minutes I spotted at least 8 types of bee: two bumble species, two Andrena species, one species of Habropoda, one Halictus, two Nomada species, and two other species I couldn’t identify. It’s the Nomada that are the cuckoo bees (also known as cleptoparasites).
Nomada isn’t the only genus of cuckoos, but it is one of the largest. Once the egg hatches, the Nomada larva destroys the egg or larva left by the host bee and then uses the pollen provision to grow on. The different species of cuckoo bees vary in their selection of hosts and their growth pattern, but they all invade the nests of other bees.
The Nomada shown is probably parasitic on the Andrena seen in the last two photos. I can’t be absolutely certain because I never found any nests, but the fact they are active at the same time and place is a good clue.
Just love those photographs.
Rusty, I learn so much from you. Trustworthy, science-based information presented in easily readable format. Thank you.
Perfect timing. Just got a call from a concerned parent about a large number of “bees” hovering close to the ground in their backyard, the Andrena or mining bee was emerging and or building their nests in the ground, the parent sent me a picture and confirmed it was in fact this species. They wanted to know how to get rid of them and that’s when I informed them of the benefit of this solitary insect and to please, give them 2-3 weeks and they’ll be gone. Also not to worry but the hoverer is more than likely the stingless male. We need these wonderful fragile creatures. Thank you for the article!!
And thank you for trying to save them. If people only knew how gentle and how important these little guys are. Plus, they’re fun to watch.
I too, have learned much from Rusty’s posts. Prior to my foray into beekeeping, I would not hesitate to kill any bee that was not a honeybee. While outdoors yesterday, I came across a bumblebee making her way through the grass. Thanks to the educational effect of these posts, the bee continued on her journey unimpeded. Thank you Rusty, for your patient and consistent educational posts!!
Thanks Jeff. I just love the wild bees!