Black Tail Bumble Bee - Bombus melanopygus
For definitions and diagrams of bumble bee morphology please see the Montana State Entomology Collection's Bumble Bee Morphology page
. Small body size, queens 16-19 mm, workers 10-16 mm; face square, of medium head length with cheek as long as wide, tongue length medium; basitarsus of mid-leg with back far corner rounded, outer surface of hind-leg tibia flat and without hair but with a fringe of hair forming a pollen basket; hair length medium and uneven, hair yellow on face and top of head, thorax with many black hairs densely mixed in front pale band, the black band between the wings not sharply defined, the back area of thorax variably yellow; T1 yellow, T2-3 orange (sometimes with black hairs intermixed), T4-5 black (often with yellow intermixed); if T2-3 extensively black then T4-5 extensively yellow and T5 yellow on sides. Males 11-14 mm, eyes similar in size and shape to any female bumble bee; antenna medium in length, flagellum 3x longer than the scape; color pattern similar to queen and worker (Koch et al. 2012, Williams et al. 2014)
Queens active February to August, workers and males March to September (Koch et al. 2012, Williams et al. 2014). In California, queens active early February to early October, workers late April to late September, males late June to early October (Thorp et al. 1983).
Please see the Montana State Entomology Collection's Key to Female Bumble Bees in Montana
. Distinguished from other Bombus
by combination of outer surface of hind-leg tibia concave and forming a pollen basket, anterior edge of thorax (scutum) to the distinct black band between the wings with mix of yellow and black hairs giving a cloudy appearance, T2-3 with red or orange hairs (T2 not intermixed with yellow) and corbicular (pollen basket) fringe hairs black (or possibly orange at the tips).
Resident Year Round
Recorded Montana Distribution
Click the map for additional distribution information.
Occurs in the Sierra Nevada and Cascade ranges in the west to the Rocky Mountains in the east, from Alaska and boreal treeline across Canada to the Mexico border (Koch et al. 2012, Williams et al. 2014). Absent from the southwestern deserts and high desert regions, with isolated occurrences in the Alaskan and eastern Arctic and western Nebraska. In Colorado, primarily above 2500 m elevation, but ranging to 4300 m (Macior 1974). In Montana, present in the mountains of the western third of the state. Considered common through much of its range.
Predominantly open grassy areas and mountain meadows, but also sagebrush steppe to alpine fell-field and tundra (Macior 1974, Bauer 1983, Shaw and Taylor 1986, Cook et al. 2011, Williams et al. 2014). In southern Alberta, B. melanopygus is found in foothill and mountain forest zones (Hobbs 1967). In southern Idaho, trapped significantly more often in areas with sagebrush canopy < 10% than where canopy > 25% (Cook et al. 2011). Also frequents commercial highbush blueberry and cranberry crops in southern British Columbia (Ratti et al. 2008). Two nests in southern Alberta were constructed in woods-meadow ecotone (Richards 1978).
Feeds on a wide variety of flowers, including Allium, Anaphalis, Arctostaphylos, Arenaria, Castilleja, Ceanothus, Dodecatheon, Ericameria, Erigeron, Eriogonum, Haplopappus, Iris, Linaria, Lupinus, Mertensia, Myosotis, Oxytropis, ,i>Pedicularis, Penstemon, Phacelia, Polygonum, Rhododendron, Rubus, Salix, Salvia, Sedum, Taraxacum, Trifolium, Vaccinium, and Wyethia (Macior 1974, Bauer 1983, Shaw and Taylor 1986, Wilson et al. 2010, Williams et al. 2014).
One of the earliest bumble bee species to begin nesting and produce males. Nests built underground, and sometimes above ground in bird houses and building insulation (Williams et al. 2014). Underground nests favored in southern Alberta (Hobbs 1967); two nests were begun 7 June. Two other nests in southern Alberta were started on 8 and 10 May (Richards 1978). Nest parasitism by cuckoo bumble bees has not been described.
- Literature Cited AboveLegend: View Online Publication
- Bauer, P.J. 1983. Bumblebee pollination relationships on the Beartooth Plateau tundra of Southern Montana. American Journal of Botany. 70(1): 134-144.
- Cook, S.P., S.A. Birch, F.W. Merickel, C.C. Lowe, and D. Page-Dumroese. 2011. Bumble bee (Hymenoptera: Apidae) community structure on two sagebrush steppe sites in southern Idaho. Pan-Pacific Entomologist 87(3): 161-171.
- Hobbs, G.A. 1967. Ecology of species of Bombus Latr. (Hymenoptera: Apidae) in southern Alberta. VI. Subgenus Pyrobombus. Canadian Entomologist 99: 1271-1292.
- Koch, J.B. and J.P. Strange. 2012. The status of Bombus occidentalis and B. moderatus in Alaska with special focus on Nosema bombi incidence. Northwest Science 86: 212-220.
- Macior, L.M. 1974. Pollination ecology of the Front Range of the Colorado Rocky Mountains. Melanderia 15: 1-59.
- Ratti, C.M., H.A. Higo, T.L. Griswold, and M.L. Winston. 2008. Bumble bees influence berry size in comercial Vaccinium spp. cultivation in British Columbia. Canadian Entomologist 140(3): 348-363.
- Richards, K.W. 1978. Nest site selection by bumble bees (Hymenoptera: Apidae) in southern Alberta. Canadian Entomologist 110(3): 301-318.
- Shaw, D.C. and R.J. Taylor.1986. Pollination ecology of an alpine fell-field community in the North Cascades. Northwest Science 60:21-31.
- Thorp, R.W., D.S. Horning, and L.L. Dunning. 1983. Bumble bees and cuckoo bumble bees of California (Hymenoptera: Apidae). Bulletin of the California Insect Survey 23:1-79.
- Williams, P., R. Thorp, L. Richardson, and S. Colla. 2014. Bumble Bees of North America. Princeton, NJ. Princeton University Press.
- Wilson, J.S., L.E. Wilson, L.D. Loftis, and T. Griswold. 2010. The montane bee fauna of north central Washington, USA, with floral associations. Western North American Naturalist 70(2): 198-207.
- Additional ReferencesLegend: View Online Publication
Do you know of a citation we're missing?
- Dolan, A.C., C.M. Delphia, K.M. O'Neill, and M.A. Ivie. 2017. Bumble Bees (Hymenoptera: Apidae) of Montana. Annals of the Entomological Society of America. 110(2): 129-144.
- Fultz, J.E. 2005. Effects of shelterwood management on flower-visiting insects and their floral resources. M.Sc. Thesis. Bozeman, MT: Montana State University. 163 p.
- Kearns, C.A. and J.D. Thomson. 2001. The Natural History of Bumble Bees. Boulder, CO. University Press of Colorado.
- Reese, E.G., L.A. Burkle, C.M. Delphia, and T. Griswold. 2018. A list of bees from three locations in the Northern Rockies Ecoregion (NRE) of western Montana. Biodiversity Data Journal 6: e27161.
- Simanonok, M. 2018. Plant-pollinator network assembly after wildfire. Ph.D. Dissertation. Bozeman, MT: Montana State University. 123 p.
- Simanonok, M.P., and L.A. Burkle. 2014. Partitioning interaction turnover among alpine pollination networks: Spatial temporal, and environmental patterns. Ecosphere 5(11):149.
- Additional Sources of Information Related to "Insects"