Early spring wildflowers, like the Virginia Spring Beauty (Claytonia virginica), are an important source of food for a host of small bees and other insects. Many insects gather pollen from these flowers and in doing so help to pollinate the plants. One species, the Spring Beauty Miner Bee (Andrena erigeniae), is so specialized that it reportedly feeds only on this ephemeral flower.
According to the Bug of the Week website that featured this species in an article, “Using jaws and legs the female bees excavates a gallery in the soil, leaving a small pile of dirt near the entrance hole. This gallery can be as long as 15 centimeters and contain numerous lateral brood chambers. During the daytime she forages for pollen on flowers of spring beauties, which apparently are the sole source of food for her brood. Pollen from these blossoms is formed into balls and placed into brood chambers…As brood chambers are built and provisioned with pollen, the bee deposits a single egg on a pollen cake. During spring and early summer developing larvae consume the pollen, and later in summer they will form pupa. By late autumn development of the adult is complete and winter is spent in the adult stage within the brood chambers. Newly minted adults emerge each spring coincident with the appearance of spring beauty’s’ blossoms.” Wow!
On Monday I was fortunate to capture a shot of a Spring Beauty Miner Bee in action gathering pollen. If you look closely at the image, you will see how the tiny bee has collected pollen on its back legs.
Last year I posted an image of a Cuckoo Bee on the same kind of flower. That bee does not collect pollen. Instead it enters the nests of a host and lay eggs there, stealing resources that the host has already collected. From what I understand the cuckoo bee waits for the miner bee to leave its burrow and then lays its egg there. The offspring of the cuckoo bee eats the pollen in the burrow and then eats the larva of the miner bee. Yikes!
© Michael Q. Powell. All rights reserved.
Mike Powell 