Half-black Bumble Bee

Image © Lynette Elliott

Bombus vagans

Common name:
Half-black bumble bee


A common bumble bee found throughout Wisconsin.  Queens and workers of this species are typically a bit smaller than average.

Physical Appearance

Hair medium and a bit shaggy. Thorax yellow, with black circle/dot between wings. Abdominal color standard across castes: the first two segments are entirely yellow, while the remaining four are black.   Queens and workers are generally a bit smaller than other common species.  Males with similar color patterns, but an obvious yellow beard on the middle of the face.  Some male morphs have some to an entirely yellow abdomen and thorax, which can be easily confused as B. perplexus.

Color Morphs




Activity Period

Similar to B.impatiens, long lived colonies.  Largest densities possible during July as all three castes are present.  Look for new queens in late July and early August.


The half-black bumble bee can be seen throughout Wisconsin.  It is likely the third to forth most common species we have.

Conservation Status

Seemingly stable, and potentially increasing in abundance.  More work is needed to establish a more accurate conservation status for this species.

Preferred flowers

(Beard Tongue)



Can be confused with...

Bombus perplexus

Bombus affinis (queens and patch-less workers)