The expanding Pacific Northwest range of Bombus impatiens Cresson and its establishment in Washington State

  • Chris LooneyEmail author
  • James P. Strange
  • Maggie Freeman
  • David Jennings
Invasion Note


Bombus impatiens, the common eastern bumble bee, is the first bumble bee established outside of its native range in North America. Native to the eastern portion of the continent, the species was imported to British Columbia in the early 2000s for greenhouse pollination and subsequently became established in the wild. Here we report on the continuing expansion of its range in the Pacific Northwest, including the detection of gynes and workers in Washington State. Sightings of B. impatiens in the region have become increasingly common based on various Internet mapping and reporting sites. The species has been observed about 30 km south of the British Columbia border, or 60 km from the first British Columbia detections. Species distribution models indicate that the Puget Sound and Willamette Valley are suitable habitat, and the bee will likely continue to expand its range southward towards California. The potential impacts of B. impatiens in the region are unknown and will be monitored in future research.


Common eastern bumble bee Range expansion Pollinators Citizen science Commercial colonies 



We thank Beth Chisholm (Whatcom County Master Gardener program coordinator), Caitie Blethen (San Juan County Master Gardener program coordinator), Eliza Habegger (San Juan County Land Bank) and numerous volunteers for deploying blue-vane traps. Rian Wojahn (WSDA) provided Japanese beetle bycatch for analysis. We thank Bumble Bee Watch,, and for supplying data, and are grateful for all of the volunteer participants who gathered those data.

Supplementary material

10530_2019_1970_MOESM1_ESM.pdf (262 kb)
Supplementary material 1 (PDF 261 kb)


  1. Aizen MA, Smith-Ramirez C, Morales CL, Vieli L, Saez A, Barahona-Segovia RM, Arbetman MP, Montalva J, Garibaldi LA, Inouye Harder LD (2018) Coordinated species importation policies are needed to reduce serious invasions globally: the case of alien bumblebees in South America. J Appl Ecol 2018:1–7Google Scholar
  2. Arbetman M, Meeus I, Morales CL, Aizen MA, Smagghe G (2013) Alien parasite hitchhikes to Patagonia on invasive bumblebee. Biol Invasions 15:489–494CrossRefGoogle Scholar
  3. Boria RA, Olson LE, Goodman SM, Anderson RP (2014) Spatial filtering to reduce sampling bias can improve the performance of ecological niche models. Ecol Model 275:74–77CrossRefGoogle Scholar
  4. (2018) Accessed 10 June 2018
  5. Cameron SA, Lozier JD, Strange JP, Koch JB, Cordes N, Solter LF, Griswold TL (2011) Patterns of widespread decline in North American bumble bees. Proc Nat Acad Sci 108:662–667CrossRefGoogle Scholar
  6. Cameron SA, Lim HC, Lozier JD, Duennes MA, Thorp R (2016) Test of the invasive pathogen hypothesis of bumble bee decline in North America. Proc Natl Acad Sci USA 113:4386–4391CrossRefGoogle Scholar
  7. Canadian Food Inspection Agency (2013) Bumblebee sector guide to the national bee farm-level biosecurity standard. Accessed 01 Dec 2018
  8. Colla SR, Otterstatter MC, Gegear RJ, Thomson JD (2006) Plight of the bumble bee: pathogen spillover from commercial to wild populations. Biol Conserv 129:461–467CrossRefGoogle Scholar
  9. Cordes N, Huang WF, Strange JP, Cameron SA, Griswold TL, Lozier JD, Solter LF (2012) Interspecific geographic distribution and variation of the pathogens Nosema bombi and Crithidia species in United States bumble bee populations. J Invertebr Pathol 109:209–216CrossRefGoogle Scholar
  10. Dainat B, vanEngelsdorp D, Neumann P (2012) Colony collapse disorder in Europe. Environ Microbiol Rep 4:123–125CrossRefGoogle Scholar
  11. Elith J, Phillips SJ, Hastie T, Dudík M, Chee YE, Yates CJ (2011) A statistical explanation of MaxEnt for ecologists. Divers Distrib 17:43–57CrossRefGoogle Scholar
  12. Fick SE, Hijmans RJ (2017) Worldclim 2: new 1-km resolution climate surfaces for global land areas. Int J Climatol 37:4302–4315CrossRefGoogle Scholar
  13. Flanders RV, Wehling WF, Craghead AL (2003) Laws and regulations on the import, movement and release of bees in the United States. In: Strickler K, Cane JH (eds) For nonnative crops, whence pollinators of the future?. Thomas Say Publications in Entomology, Lanham, pp 99–111Google Scholar
  14. (2018) GBIF occurrence download. Accessed 30 Apr 2018
  15. Goulson D, Lye GC, Darvill B (2008) Decline and conservation of bumble bees. Ann Rev Entomol 53:191–208CrossRefGoogle Scholar
  16. Graystock P, Yates K, Evison SEF, Darvill B, Goulson D, Hughes WOH (2013) The Trojan hives: pollinator pathogens, imported and distributed in bumblebee colonies. J Appl Ecol 50:1207–1215Google Scholar
  17. Grixti JC, Wong LT, Cameron SA, Favret C (2009) Decline of bumble bees (Bombus) in the North American Midwest. Biol Conserv 142:75–84CrossRefGoogle Scholar
  18. Higes M, Martín-Hernández R, Garrido-Bailón E, González-Porto AV, García-Palencia P, Meana A, Del Nozal MJ, Mayo R, Bernal JL (2009) Honeybee colony collapse due to Nosema ceranae in professional apiaries. Environ Microbiol Rep 1:110–113CrossRefGoogle Scholar
  19. (2018) Accessed 10 June 2018
  20. Koch JB, Looney C, Sheppard WS, Strange JP (2016) Range extension of two bumble bee species (Hymenoptera: Apidae) into Olympic National Park. NW Sci 90(2):228–234Google Scholar
  21. McFrederick QS, LeBuhn G (2006) Are urban parks refuges for bumble bees Bombus spp. (Hymenoptera: Apidae)? Biol Cons 129:373–382CrossRefGoogle Scholar
  22. Morales CL (2007) Introducción de abejorros (Bombus) no nativos: causas, consecuencias ecológicas y perspectivas. Ecología Austral 17:51–65Google Scholar
  23. Peterson AT, Soberón J, Pearson RG, Anderson RP, Martínez-Meyer E, Nakamura M, Araújo MB (2011) Ecological niches and geographic distributions. Monographs in population biology 49. Princeton University Press, Princeton, NJCrossRefGoogle Scholar
  24. Phillips SJ, Dudík M, Schapirem RE (2018) Maxent software for modeling species niches and distributions (version 3.4.1). Accessed 25 Mar 2019
  25. Ratti CM, Colla SR (2010) Discussion of the presence of an eastern bumble bee species (Bombus impatiens Cresson) in western Canada. Pan Pac Entomol 86:29–31CrossRefGoogle Scholar
  26. Ruz L (2002) Bee pollinators introduced to Chile: a review. In: Kevan P, Imperatriz Fonseca VL (eds) Pollinating bees—the conservation link between agriculture and nature. Ministry of Agriculture, Brasilia, pp 155–167Google Scholar
  27. Strange JP, Tripodi AD (2019) Characterizing bumble bee (Bombus) communities in the United States and assessing a conservation monitoring method. Ecol Evol 00:1–9. Google Scholar
  28. The Xerces Society, Wildlife Preservation Canada, York University, University of Ottawa, The Montreal Insectarium, The London Natural History Museum, BeeSpotter (2018) Bumble Bee Watch, a collaborative website to track and conserve North America’s bumble bees. Accessed 10 June 2018
  29. Torretta JP, Medan D, Abrahamovich AH (2006) First record of the invasive bumblebee Bombus terrestris (L.) (Hymenoptera: Apidae) in Argentina. Trans Am Entomol Soc 132:285–289CrossRefGoogle Scholar
  30. vanEnglesdorp DJ, Evans JD, Saegerman C, Mullin C, Haubruge E, Nguyen BK, Frazier M, Frazier J, Cox-Foster D, Chen Y, Underwood R, Tarpy DR (2009) Colony collapse disorder: a descriptive study. PloS ONE 4(8):e6481CrossRefGoogle Scholar
  31. Velthuis HHW, van Doorn A (2006) A century of advances in bumblebee domestication and the economic and environmental aspects of its commercialization for pollination. Apidologie 37:421–451CrossRefGoogle Scholar
  32. Williams PH (1982) The distribution and decline of British bumble bees (Bombus Latr.). J Apic Res 21:236–245CrossRefGoogle Scholar
  33. Yokoyama J, Inoue MN (2010) Status of the invasion and range expansion of an introduced bumblebee, Bombus terrestris (L.), in Japan. Appl Entomol Zool 45:21–27CrossRefGoogle Scholar

Copyright information

© This is a U.S. government work and its text is not subject to copyright protection in the United States; however, its text may be subject to foreign copyright protection 2019

Authors and Affiliations

  1. 1.Washington State Department of AgricultureOlympiaUSA
  2. 2.USDA-ARS-Pollinating Insect Research UnitNorth LoganUSA
  3. 3.Washington State Butterfly AssociationSeattleUSA

Personalised recommendations