The Common Eastern Bumble Bee is ground-nesting species that is often found in large colonies of up to 450 workers (
Beespotter 2011). It is native to eastern North America, where it is found "basically east of the 100th Meridian (maybe the 103rd)" (Thorp pers.comm. 2012). While some bumble bee species (e.g.
Bombus occidentalis and
Bombus affinis) have declined throughout their range,
Bombus impatiens, by contrast, has increased in abundance in Canada (Ratti and Colla 2010).
Additionally, Bombus impatiens is now used as a greenhouse pollinator, and this has led to escape and establishment in some areas. Ratti and Colla (2010) provide some insights into this: "In recent decades, bumble bees have been domesticated in North America to pollinate greenhouse and field crops such as tomato and sweet pepper (Velthuis & van Doorn 2006). Initially two species were reared commercially for this purpose; B. occidentalis in the west and B. impatiens in the east (Whittington & Winston 2004). After an apparent collapse of both managed and wild B. occidentalis populations, B. impatiens has since been used in parts of western North America to meet greenhouse pollination needs (Evans et al. 2009, Whittington & Winston 2004)."
This species was reported by Ratti and Colli (2010) as present in fields outside of greenhouses in the Fraser Valley in 2003 and 2004. Cannings (2011) indicates that it has been brought into BC for pollination since 1999 and escaped from greenhouses, and is now established. Photo documentation of this species occurrence in BC is provided in the E-Fauna BC photo gallery.
Editor's Note:
Bumble bee researchers are working to further document this species' establishment in BC and the photos provided in the E-Fauna photo gallery can aid in this research. In particular, if additional detail is provided with each photo, this will be useful to the research. Researcher Robbin Thorp says: "If the [E-Fauna] photographers can provide any information as to the distance of [their] sighting from the nearest tomato greenhouses this would be extremely useful information as well."
Recommended References:
Ratti, Claudia M. and Sheila R. Colla. 2010. Discussion of the presence of an eastern bumble bee species (Bombus impatiens Cresson) in western Canada. The Pan-Pacific Entomologist 86(2):29–31.
Vernal pool flowers and their specialist bee pollinators (by Robbin Thorp)
