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Ecology of Species of Bombus Latr. (Hymenoptera: Apidae) in Southern Alberta. II. Subgenus Bombias Robt.1

Published online by Cambridge University Press:  31 May 2012

G. A. Hobbs
Affiliation:
Canada Agriculture Research Station, Lethbridge, Alberta

Abstract

In southern Alberta, the distribution of Bombus (Bombias) auricomis is confined to wooded areas whereas that of B. (Bombias) nevadensis encompasses prairie and wooded areas. Perhaps B. nevadensis survives on the prairie because it hibernates well below the surface of the soil.

When given equal opportunity to nest in surface or underground hives, B. nevadensis nested in three surface and 18 underground hives. Both species began to establish nests between mid-May and mid-June.

Both species laid one egg per cell in all broods, vertically in the first brood and horizontally in later broods. Larvae were fed individually in all instars of all broods, except perhaps during early instars of the first brood when pollen was packed beneath them through pockets made at both ends of the brood mass.

The eggs in the first brood layer were usually laid within 4 days. The cells beneath the shallow incubation groove were usually the first made and the ones from which adults first emerged. Queens of B. nevadensis required about a month to rear sufficient workers to take care of the foraging duties of the new colonies. Egg cells of succeeding broods were built side by side in groups or lines on cocoons of previous broods and were not primed with pollen.

Both species were prolific producers of wax. More pots for the storage of honey and pollen were added as colonies increased in size.

Colonies of both species were usually small, apparently because the queens usually found time to rear only one brood of workers and perhaps because only one egg was laid in each cell. The largest colony, of B. nevadensis, produced 139 individuals. The workers of a brood sometimes varied greatly in size. The workers of succeeding broods were progressively larger, the last ones produced being almost as large as queens. Males of B. nevadensis mated by grasping the queens when they were flying, then copulating on the ground. After mating, queens hibernated at a depth of about 3 inches in the soil.

Males and females of Psithyrus insularis were reared in nests of B. nevadensis. P. suckleyi also established in a nest of this species. The big-headed fly, Physocephala texana, was a destroyer of B. nevadensis. Ants pillaged first broods not protected with an insecticide.

Type
Articles
Copyright
Copyright © Entomological Society of Canada 1965

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References

Burks, B. D. 1951. Tribe Bombini, pp. 12471255. In Muesebeck, C. F. W., Krombein, K. V., Townes, H. K., Hymenoptera of America north of Mexico. Synoptic catalog. U.S. Dep. Agric. Monogr. No. 2.Google Scholar
Darwin, C. 1859. The origin of species by means of natural selection. Murray, London.Google Scholar
Free, J. B., and Butler, C. G.. 1959. Bumblebees. Collins, London.Google Scholar
Frison, T. H. 1917. Notes on Bombidae, and on the life history of Bombus auricomis Robt. Ann. ent. Soc. Amer. 10: 277288.CrossRefGoogle Scholar
Frison, T. H. 1918. Additional notes on the life history of Bombus auricomis Robt. Ann. ent. Soc. Amer. 11: 4349.CrossRefGoogle Scholar
Hobbs, G. A. 1964a. Phylogeny of bumble bees based on brood-rearing behaviour. Canad. Ent. 96: 115116.CrossRefGoogle Scholar
Hobbs, G. A. 1964b. Ecology of species of Bombus Latr. (Hymenoptera: Apidae) in southern Alberta. I. Subgenus Alpinobombus Skor. Canad. Ent. 96: 14651470.CrossRefGoogle Scholar
Hobbs, G. A., Nummi, W. O., and Virostek, J. F.. 1962. Managing colonies of bumble bees (Hymenoptera: Apidae) for pollination purposes. Canad. Ent. 94: 11211132.CrossRefGoogle Scholar
Holm, S. N., and Haas, H.. 1961. Erfahrungen und resultate drejahriger domestikations-versuohe mit hummeln (Bombus Latr.). Albrecht-Thaer-Archiv. 5: 282304.Google Scholar
Horber, E. 1961. Beitrag zur domestikation der hummeln. Vierteljahrsschr. naturforsch. Ges. Zurich 106: 424447.Google Scholar
Plath, O. E. 1927. Nesting habits of some New England bumble bees. Psyche, Camb., Mass. 34: 122128.CrossRefGoogle Scholar
Salt, R. W. 1959. Role of glycerol in the cold-hardening of Bracon cephi (Gahan). Canad. J. Zool. 37: 5969.CrossRefGoogle Scholar
Sladen, F. W. L. 1912. The bumblebee. Macmillan, London.Google Scholar