Bombus (Pyrobombus) impatiens Cresson

Tripodi, Amber D. & Szalanski, Allen L., 2015, The bumble bees (Hymenoptera: Apidae: Bombus) of Arkansas, fifty years later, Journal of Melittology 2015 (50), pp. 1-17 : 12-13

Bombus (Pyrobombus) impatiens Cresson

‘Common Eastern Bumble Bee’

The occurrence of B. impatiens has more than tripled between the historic (21%) and contemporary sample periods (72%, Fig. 3). This is consistent with other reports of B. impatiens throughout its range ( Cameron et al., 2011; Colla & Packer, 2008; Colla et al., 2012). The UAAM collection holds two specimens collected between our historical and contemporary periods: Polk Co., June 4, 1963 and Saline Co., August 17, 1976. In the United States, B. impatiens is the only bumble bee species currently mass-reared for pollination services and has been commercially available since 1990 ( Velthuis & van Doorn, 2006). The ecological repercussions of commercial bumble bee trafficking are largely unknown. The greatest concern has been the potential for pathogen spillover, the transmission of diseases from commercial colonies to wild ones. Commercial bumble bee colonies are known to support heavier loads of pathogens, such as the intestinal protozoa Crithidia bombi Lipa & Triggiani and Nosema bombi Fantham & Porter , and parasites, such as the tracheal mite Locustacarus buchneri (Stammer) , than their wild counterparts ( Colla et al., 2006). Wild bees foraging near greenhouses in Canada which utilize commercial bumble bees are more likely to be infected with C. bombi and N. bombi than wild bees located far from greenhouses ( Colla et al., 2006). This pathogen spillover from commercial bumble bees to wild populations may pose a threat to the stability of wild bumble bee populations. The commercial use of B. impatiens may also have another potential ecological impact that has remained unexplored: artificially increasing the local abundance of the commercial species through augmentation. If this were the case, we might expect B. impatiens to be less common in wildlands than in areas near agricultural development. Indeed, B. impatiens was rarely encountered in surveys of Arkansas grasslands from 2002 to 2008 ( Warriner, 2011), in spite of its recent increase in county-level records. Whether or not the commercial trafficking of B. impatiens has influenced localized increases in Arkansas and elsewhere is unknown, but it is a notion that warrants further study.

GLOSSA LENGTH: Short (4.74 ± 0.62 mm).

ADULT ACTIVE PERIOD: Late season with an intermediate active period (75 days). Majority: mid-July through early October; Earliest: April 22; Latest: October 20.

PREFERRED PLANTS: Solidago speciosa Nutt. (showy goldenrod, Asteraceae ), Symphyotrichum Nees (aster, Asteraceae ), S. integrifolium (wholeleaf rosinweed, Asteraceae ), Solidago (goldenrod, Asteraceae ), P. pilosum (Michx.) Pers. (whorled mountainmint, Lamiaceae ), V. alternifolia (Linnaeus) Britt. ex Kearney (wingstem, Asteraceae ), V. virginica (white crownbeard, Asteraceae ), S. altissima ( Canada goldenrod, Asteraceae ), Salvia azurea Michx. ex Lam. (azure blue sage, Lamiaceae ).