Key Differences Between Queen and Worker Bumblebees

Bumblebees have a fascinating social structure centered around a single queen. But what sets her apart from the masses of workers in the colony? Let’s explore the unique traits and roles of queen and worker bumblebees

Appearance

The most noticeable difference is size. Queen bumblebees have larger, elongated abdomens compared to the more compact workers. This allows them to carry more eggs. Queens also possess small, rounded heads whereas workers have broader, rectangular heads.

Another distinguishing feature is coloration Queens have two distinct yellow bands on the thorax and a solid buff-colored abdomen Workers show one yellow band on a primarily black thorax and have white abdomens with a faint buff line separating them from the rest of the body,

Roles

The queen’s sole duty is to mate and lay eggs while workers take care of everything else. The queen starts the colony in spring by finding a nest and laying her first batch of eggs. She then relies on the emerging workers to find food, defend the nest, and tend to the larvae she produces.

Workers spend their time collecting nectar and pollen, regulating the temperature of the nest feeding the larvae, and protecting the colony from predators. The queen remains in the nest while workers regularly venture out to forage.

Reproduction

Queens are the only bumblebees capable of reproducing. They mate with males early in spring before starting a nest. The queen can control whether eggs are fertilized to produce female workers or unfertilized to produce male drones.

Workers are sterile females with underdeveloped reproductive organs. Their ovaries only become active if the queen dies and no larvae are young enough to be raised as a replacement.

Lifespan

Queens enjoy the longest lifespans of 1-2 years. They survive through winter hibernation alone and emerge to start a new colony in spring. Workers born in spring and summer may only live 4-6 weeks. Those that emerge later in fall can survive several months, overwintering in the nest until dying the following spring.

Stingers

Like all bumblebees, queens have smooth stingers and can sting repeatedly without injury. Workers share this same stinger structure. The queen mainly uses her stinger to battle rival queens. For workers, stinging is reserved for defense against predators.

Interactions with Humans

Queens and workers vary in their response to humans. Established queens often become quite docile as they devote energy to egg-laying. In contrast, workers may show more defensive behaviors like buzzing, stinging, and buzzing when their nest is disturbed.

Colony Development

In early spring, queens emerge from hibernation and begin searching for nest sites. Once a suitable location is found, the queen gathers pollen to create a honey pot and lays her first batch of eggs. She cares for these larvae as they develop into adult workers.

As more workers emerge, they take over the nest-building duties and foraging to feed the queen and new brood. A mature bumblebee colony can house a few hundred workers by late summer.

Swarming

Unlike honeybees, bumblebee colonies only live one season. At the end of summer, the queen stops laying fertilized eggs andyoung queens and males are produced. Mated new queens depart to hibernate while the old queen, workers, and males die out as winter approaches.

Queen vs. Worker Bumblebees

While the queen and her daughter workers are both female bumblebees, they carry out very different duties critical to the colony’s survival and propagation. Their varying physical traits and behaviors reflect an advanced social structure that relies on this separation of reproductive and non-reproductive roles.