Like honey bees, most species of bumble bee are eusocial (living in a cooperative group). However, unlike honey bee colonies that can live for many years, bumble bee colonies are annual, meaning that new colonies are started from scratch every year. Only the new, future queens will survive the winter. These special ladies (called gynes) will spend the autumn drinking a lot of nectar to build up their fat reserves. They will then mate and look for a safe place to spend the winter–usually a small hole in the ground, just big enough for one, called a hibernacula.
Once safely underground, the bee’s metabolic rate drops to conserve energy, and her body produces antifreeze compounds to protect her from the cold. She won’t eat or leave the nest until environmental cues let her know that spring has sprung!
The new queens will be very hungry after the long winter, so providing plenty of early-spring nectar resources is crucial to support a healthy population. The blooms of native trees, shrubs and spring ephemerals are just the ticket to provide the energy they need to build a new team of pollinating champions.
Sleep tight, ladies–spring is on the way!
Photo: © Heather Holm