Life Cycle of The Queen Bumblebee

How She Survives the Lonely Winter and Repopulates the Colony

Bumblebee workers live only from spring to fall.
Bumblebee workers live only from spring to fall. Katja Schulz/Flickr

There are more than 255 species of bumblebees worldwide. All share similar physical features: they are round and fuzzy insects with short wings which flap back and forth rather than up and down. Unlike honey bees, they are not agressive, are unlikely to sting, and produce relatively little honey. Bumblebees are, however, major pollinators. Beating their wings as fast as 130 times per second, their large bodies vibrate very quickly. This movement releases pollen, helping crops to grow.  

The health and well-being of a bumblebee colony depends very largely on the queen bee. The queen, alone, is responsible for bumblebee reproduction; the other bees in the colony spend the majority of their time caring for the queen and her offspring.

Unlike honey bees, which overwinter as a colony by clustering together, bumblebees (Genus Bombus) live from spring to fall. Only the fertilized bumblebee queen will survive the winter by finding shelter from the freezing temperatures. She spends the long, cold winter hidden away alone. 

The Queen Bumble Bee Emerges

In spring, the queen emerges and searches for a suitable nest site, typically in an abandoned rodent nest or small cavity. In this space, she builds a ball of moss, hair, or grass, with a single entrance. Once the queen has constructed a suitable home, she prepares for her offspring.

Preparing for Bumble Bee Offspring

The spring queen builds a wax honey pot and provisions it with nectar and pollen. Next, she collects pollen and forms it into a mound on the floor of her nest. She then lays eggs in the pollen and coats it with wax secreted from her body.

Like a mother bird, the Bombus queen uses the warmth of her body to incubate her eggs. She sits on the pollen mound and raises her body temperature to between 98° and 102° Fahrenheit. For nourishment, she consumes honey from her wax pot, which is positioned within her reach. In four days, the eggs hatch.

The Queen Bee Becomes a Mother

The bumblebee queen continues her maternal care, foraging for pollen and feeding her offspring until they pupate. Only when this first brood emerges as bumblebee adults can she quit the daily tasks of foraging and housekeeping.

For the remainder of the year, the queen concentrates her efforts on laying eggs. Workers help incubate her eggs, and the colony swells in number. At the end of summer, she begins laying some unfertilized eggs, which become males. The bumblebee queen allows some of her female offspring to become new, fertile queens.

The Bumble Bee Circle of Life

With new queens ready to continue the genetic line, the bumblebee queen dies, her work complete. As winter approaches, the new queens and males mate. The males die soon after mating. The new generations of bumblebee queens seek shelter for the winter and wait until the following spring to begin new colonies.

Many species of bumblebees are now endangered. There are many possible reasons for this, ranging from pollution and habitat loss to climate change.