Other Common Names
Andrenid Bee, Solitary Bee, Burrowing Bee, Ground-nesting Bee
Numbers
Nomina Insecta Neartica lists 12 genera and over 1200 North American species, most belonging to genera
Andrena and
Perdita.
Identification
Head almost as large as thorax; most species have a short, pointed tongue. Abdomen usually longer than head and thorax combined. Wings smoky to dark. Pollen brush on most of hind leg.
(1)Habitat
Nests in burrows in the ground, often in aggregations, usually in areas of sparse vegatation.
(2)Food
Adults drink nectar. Larva feeds on nectar and pollen.
(1)Life Cycle
Female digs long branching tunnel in soil, prepares brood cell at the end of each branch, and stocks cells with pollen balls and nectar. 1 egg is laid on pollen ball in each cell, then cell is sealed. Larvae develop rapidly and pupate in cells. 1 generation a year.
(1)Remarks
Many small, ground-nesting bees observed in areas of sandy soil are members of the family, Andrenidae. Characteristics of this family (of which there are approximately 3000 species) are: Small size, 20 mm, (or smaller) brown to black in color, and nesting in a burrow in areas of sparse vegetation, old meadows, dry road beds, sandy paths. Although the nests are built in close proximity of one another, the bees are solitary (each female capable of constructing a nest and reproducing). Many species are active in March and April when they collect pollen and nectar from early spring blooming flowers. The female bee digs a hole 2-3 inches deep excavating the soil and leaving a pile on the surface. She then digs a side tunnel that ends in a chamber (there are about 8 chambers per burrow). Each chamber is then filled with a small ball of pollen and nectar. An egg is laid on the top of each pollen ball and the female seals each brood chamber. The emerging larval bees feed on the pollen/nectar ball until they pupate.
Print References
"Peterson's Field Guide to Insects", pages 354-357.
(2)
"National Audubon Society Field Guide to North American Insects & Spiders", pages 854-856, plate 503.
(1)
"American Insects: A Handbook of the Insects of America North of Mexico"
(3), p. 601.
Internet References
University of Florida - has a photo and information on Andrenidae
New Brunswick's (Canada) website - has info on the Andrenidae life cycle and includes diagrams of their burrows
The Insects of Cedar Creek - has photos of many species and information
