The bumble bees of Florida

Bumble bees are large, social bees which produce annual colonies. Mated queens overwinter in the soil and emerge from hibernation in early Spring when they feed on spring flowers and search for a suitable location, such as a former rodent nest in the soil, to begin their colonies. Once a nest site is found, she collects pollen and lays her first brood of worker eggs. Workers emerge about 21 days after the eggs are laid and take over the duties of pollen and nectar collection as well as colony defense. The size of the workers increases with each new brood. The third caste of bumble bees, the males, are usually produced in midsummer. Bumble bees are easily recognized by the corbicula or pollen basket on the hind tibiae in the females. Honey bees are the only other bees in Florida with this structure but are easily recognized by their smaller size, hairy eyes and lack of hind tibial spurs. The five species of bumble bees found in Florida are usually separated by the pattern of the black and yellow pubescence. The closely related parasitic Psithyrus are easily distinguished by the lack of the corbicula.

All bumble bees found in Florida range north into Canada (Laverty & Harder, 1988). Bumble bees become rarer in southern Florida. None are known from the Keys. Two species (Bombus griseocollis & B. pennsylvanicus) are known from Collier County whereas a third species (B. impatiens) has been collected in West Palm County. These are beneficial insects which pollinate many native and ornamental plants. They can sting severely, so problem nests near human dwellings should be removed by experienced pest control operators .