The bumble bee queen is the central figure of her colony, solely responsible for establishing a new nest each spring and ensuring its continuation. Her journey from solitary hibernation to leading a thriving community highlights her important role.
Appearance and Identification
A bumble bee queen is distinguished from worker and male bees primarily by her larger size, often ranging from 20 to 33 mm in length, comparable to a quarter. Her coloring resembles that of worker bees, with black bodies, yellow stripes, and a thick yellow collar. However, her robust build indicates her status.
Female bumble bees, including queens, possess pollen baskets on their legs, which are absent in males. Female bumble bees also have 12 segments on their antennae, while males have 13. These characteristics, especially her larger size and early spring foraging, aid in her identification.
The Queen’s Role in the Colony
The bumble bee queen’s primary function is reproduction, as she is the only member capable of laying fertilized eggs. She stores sperm from mating in the previous year within a spermatheca, allowing her to control egg fertilization. Fertilized eggs become diploid females, while unfertilized eggs develop into haploid males.
Beyond egg-laying, the queen initially forages and cares for her first brood, incubating and feeding them nectar and pollen. She constructs wax cells for her eggs and creates “brood clumps” by laying eggs into pollen balls. Her body also produces pheromones, chemical signals that regulate colony behavior, suppress worker reproduction, and promote social cohesion. These pheromones influence worker behavior.
Annual Life Cycle
The annual life cycle of a bumble bee colony begins in early spring when the queen emerges from underground hibernation, in late March to early May depending on the climate. She is the first bumble bee seen in spring after overwintering. She feeds on early blooming flowers, consuming nectar for energy and pollen for ovarian development.
After a few weeks of solitary foraging and building fat reserves, the queen searches for a suitable nest site, using pre-existing cavities like abandoned rodent burrows or dense grass. Once chosen, she constructs wax pots for nectar storage and lays her first batch of eggs directly onto pollen provisions. The queen cares for this initial brood, foraging, incubating, and defending until the first workers emerge.
Four to five weeks after the eggs are laid, the first worker bees emerge from their cocoons. These workers take over foraging, nest maintenance, and caring for subsequent broods, allowing the queen to focus solely on egg-laying. The colony grows throughout the summer, peaking in late summer with hundreds of individuals.
In late summer or early fall, the queen begins to lay unfertilized eggs that develop into males, and fertilized eggs that become new queens. These new queens and males leave the nest to mate. After mating, the new queens feed to build fat reserves for winter. The original queen, worker bees, and males die as the weather cools, leaving only the newly mated queens to find underground locations to hibernate until the following spring.