New York Natural Heritage Program
American Bumble Bee
Bombus (Thoracobombus) pensylvanicus (De Geer, 1773)
Insects

Identifying Characteristics [-]
American bumble bee queens and workers have yellow hair on the front of the thorax and abdominal segments two and three and the rear edge of segment one. Other areas are black. Males have similar coloration to females, with the addition of yellow hair on the rear of the thorax and yellow on abdominal segments one through five (Colla et al. 2011, Evans 2009).
American Bumble Bee Images
click to enlarge
The Best Time to See
Bumble bee queens hibernate over the winter, emerge in the spring, locate a nest site, and rear young (workers, males, and new queens). After new queens and males mate, all males, workers, and old queens die by the beginning of winter and new queens settle into sites to overwinter (Schweitzer et al. 2012).
J F M A M J J A S O N D
Active Reproducing
The time of year you would expect to find American Bumble Bee active (blue shading) and reproducing (orange shading) in New York.
Similar Species
  • Black and Gold bumble bee (Bombus auricomus)
    Black and gold bumble bees have yellow hair on top of their head, while American bumble bees have black hair here. Both species (with workers and queens) have yellow hair on abdominal segments two and three, but American bumble bees have yellow at the rear edge of the first segment too (Evans et al. 2009).
  • Yellowbanded bumble bee (Bombus (Bombus) terricola)
    Yellowbanded workers and queens have yellow on abdominal segments two and three and a fringe of brownish yellow hair on the far edge of the fifth segment. American bumble bees have yellow at the rear edge of the first abdominal segment as well as segments two and three and lack the fringe on the fifth segment. Male Yellowbanded have black hair on the rear of the thorax, but American males have yellow hair here (Evans et al. 2009).