Species Bombus impatiens - Common Eastern Bumble Bee

Needs to be clarified. Perhaps named for the plant genus Impatiens, which it often visits, but some have suggested that the specific epithet "impatiens" makes this the impatient bumble bee.

Author: Cresson, 1863.

queen: body length 17-21 mm

male: 12-17 mm

worker: 8.5-16 mm

Pale T1 and all black T2 (but some individuals have a considerable amount of yellow on T2 and these can easily be confused with B. bimaculatus)

See detailed description of queen and male at discoverlife.org

1. Queen. 2. Worker. 3. Male. 4. Mating queen and male.

Eastern North America, from Ontario to Maine and south to south Florida (Miami area). Common on Atlantic coast; much less common near the western edge of its range (eastern ND, central NE, western KS, eastern TX).

Now widely used for greenhouse pollination in California and Mexico, far outside its native range. In the West it is used to replace the previously used western species Bombus occidentalis, because most wild and commercial populations of Bombus occidentalis disappeared after this species was developed for use by the bumble bee industry. Efforts are underway to obtain permits authorizing use of exotic B. impatiens for outdoor field pollination in California, where a very similar and very closely related species, the California native Bombus vosnesenskii, is abundant. In Mexico, B. ephippiatus is an abundant and potentially usable native alternative to B. impatiens.

Very general, including intensively farmed areas, suburbs, and highly urban areas such as downtown Chicago and Manhattan.

March to November; as early as January and February in Florida. This species overlaps broadly in flight season with all other sympatric Bombus.

A generalist, overlapping in its food requirements with other eastern short-tongued bumble bees. Very large numbers visit Solidago in the late summer and fall.

This is the most often encountered bumble bee across much of eastern North America. It has unusually large colony sizes and for this reason may be at some competitive advantage. It has an unusually long flight season and thrives across a wide range of habitats and climates ranging from the cold temperate zone (e.g., Minnesota) to the warm subtropics (south Florida). Its occurrence in the Miami area was documented long ago by Graenicher, showing that this species can establish and perpetuate itself in warm and relatively aseasonal areas. It does not require cool temperatures to overwinter.

Multiple phylogenetic studies document a very close relationship between B. impatiens, B. ephippiatus, and B. vosnesenskii, each of which is exceptionally abundant and widely distributed in its non-overlapping native range. These species of subgenus Pyrobombus are potentially important as managed pollinators in eastern North America, Mexico, and California respectively.

26 pinned adult images plus detailed description of queen and male, distribution, seasonality, flower records (discoverlife.org)

live adult images (Emily Earp and Josh Hillman, floridanature.org)

common name reference; PDF doc (Committee on Common Names of Insects, Entomological Society of America)

links to photos of male genitalia (Natural History Museum, UK)