Bumble Bees - Bombus bimaculatus

Bumble bees are big, fuzzy insects recognized by almost everyone by their robust shape and blackand yellow coloration. The common species are 3/4 inch in length or more. Like honey bees, bumble bees live in a colony where the adults care for the young (larvae) produced by a single queen. Bumble bee nests are small compared to honey bees, as each nest contains only a few hundred individuals. Also unlike honey bees, a bumble bee nest is annual and is used only one year and then abandoned.

Bumble bees usually nest in the ground in a deserted mouse nest or bird nest. Occasionally they nest in cavities within a wall or even in the clothes drier vent.

In the spring, the queen selects a nest site and starts the colony by lining an existing cavity with dry grass or moss. Then she collects a mass of pollen and moistens this with nectar to produce a stored food called "bee bread." Her first brood of offspring, numbering 5 to 20, will all be workers (daughters) who take over the colony responsibilities of nest enlargement, food gathering and storage, and feeding and caring for the larvae. The queen continues to lay eggs throughout the summer. By late summer, reproductive males and females are produced. These mate on the wing and the fertilized females move to hibernation sites in the shelter of loose bark, hollow trees or other dry, protected places to lie dormant through the winter. The males and workers still in the colony die with frost or the first hard freeze.

Along with the honey bees, bumble bees are very important pollinators of flowers. Certain plants are better pollinated by bumble bees because of their very long tongues.

If the vicinity of a bumble bee nest can be avoided, then leaving them alone and waiting for them to die in the fall would be the preferred "management" option. However, bumble bee nests are often found in yards, flowers beds, wood piles, or walls in high traffic places where the threat of being stung is great.

Trapping bumble bees is not practical and exclusion techniques may not solve the problem. When controlling bumble bees is necessary, using insecticides to poison bee colonies is the control method of choice.

Bumble bees, honey bees and yellowjackets are all controlled the same way. After determining the nest location and nest entrance during the day, wait until night to treat if possible. Wear long-sleeved hirt and trousers and tie sleeves and pants legs shut or pull your socks out over your pant cuffs.

Apply insecticide through the entrance hole. Dust formulations of insecticides are preferred (e.g., Sevin dust). Use a duster or "fling" insecticide into the hole off an old plastic spoon. Sprays and ready-to-use "wasp and hornet" aerosol sprays can also be used, but often with less satisfactory results.

Do not plug the entrance hole until all activity has stopped. Be prepared to repeat the treatment if necessary. Finally, seal shut, caulk and paint all openings in the vicinity of the old entrance.

Bumble bees are social insects whose colonies are annual and only queens fertilized the previous summer survive the winter in hibernation and emerge the following spring to found new colonies.

Bumble bees have some obvious advantages over honey bees for cage pollinating plant germplasm under cages. Bumble bee colony sizes are more conducive for pollinating small areas (e.g. under a 5' x 5' x 20' field cage). Bumble bee colonies, depending upon the species, usually contain between 30-150 workers at their peak. The minimum honey bee colony size that can remain healthy for cage pollinating plant germplasm throughout the growing season in Iowa is a colony containing around 4,000 workers. With this many individuals, supplemental feeding is a must due to the small amount of nectar and pollen available from the plants grown within the cage.

Bumble bees are also valuable in: pollinating crops during cool weather at which honey bee activity is limited, pollinating those flowers in which its large size facilitates pollen transfer (e.g. tripping flowers of some snapdragon populations), pollinating flowers with deep corolla tubes (Note: only an advantage for long tongued bumble bee species), and, pollinating plant species that benefit from having their flower sonically vibrated (i.e. buzz pollinated).

The native-to-Iowa bumble bee species, Bombus bimaculatus, has been used in pollinator studies at the Station since 1994. Rearing procedures for this insect have been developed at the station so that spring caught queens can be lab reared and used in cages for control pollination. New queens from these lab reared colonies are produced and mated, however, successfully diapausing these queens has not been entirely successful and is an area where further research is being practiced.

Bombus bimaculatus is a long-tongued species of bumble bee. Therefore, this species is useful for visiting flowers with long floral tubes. In the future, this insect may be found useful for pollinating some of the plant germplasm species maintained at the station with long floral tubes.

Bumble bees are complacent insects but every now and then someone gets stung by one or a few and has to go to the hospital due to allergies to the sting and venom in the stinger. You may have to make a several calls as soon as someone is stung to take every precaution available and ensure that persons safety. First call should be to the emergency number in your area if you know said person is allergic. Second call should be to a poison control center or other such places that have people working the phones and not call center software. Live help is key to these situations and the other persons life may very well be in the balance.

Apidae

This file was last updated: 9 May 1997

Apis indica
Apis mellifera Linnaeus
Bombus affinis Cresson
Bombus balteatus Dahlbom
Bombus b. bifarius Cresson
Bombus bimaculatus Cresson
Bombus brachycephalus Small
Bombus californicus Smith
Bombus ephippiatus Say
Bombus fervidus fervidus (Fab.)
Bombus flavifrons flavifrons Cresson
Bombus fraternus (Smith)
Bombus griseocollis (DeGeer)
Bombus impatiens Cresson
Bombus kohli Cockerell
Bombus mexicanus Cockerell
Bombus nevadensis auricomus (Robertson)
Bombus n. nevadensis Cresson
Bombus nevadensis Cresson
Bombus niger Fr.
Bombus p. pennsylvanicus (DeGeer)
Bombus pennsylvanicus sonorus Say
Bombus rufocinctus Cresson
Bombus sitkensis Nylander
Bombus sylvicola Kirby
Bombus terricola occidentalis Greene
Bombus vagans vagans Smith
Bombus vosnesenskii Rad.
Bombus spp.
Epicharis elegans Sm.
Epicharis maculata
Euglossa cordata (Linnaeus)
Eulaema dimidiata (Fabricius)
Eulaema fasciata Lepeltier
Exaerete frontalis (Guer.)
Exaerete smaragdina (Guer.)
Psithyrus ashtoni (Cresson)
Psithyrus insularis (Smith)
Psithyrus variabilis (Cresson)
Psithyrus spp.
Trigona amalthea (Oliv.)
Trigona clavipes dorsalis Smith
Trigona clavipes (Fabricius)
Trigona corvina Cockerall
Trigona fulviventris Guer.
Trigona leucogaster Cockerell
Trigona pectoralis panamensis Cockerell
Trigona pectoralis D. T.
Trigona ruficrus Latr.
Trigona testacea orizabaensis Schw.
Trigona testacea perilampoides Cresson
Trigona vaty Smith
Trigona spp.

undetermined Apidae

Breeding Bumble Bees

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