March Nature's Calendar

One of the most endearing and familiar of our insects is the first to appear after the cold winter. Look out for the brightly striped body and bumbling flight of the bumblebee this March. Bumblebees are fat and hairy, so are able to emerge from hibernation earlier in the year. They also have the ability to disengage their wings from their flight muscles, so they can quickly vibrate the flight muscles to generate heat. These adaptations mean they can take advantage of pollen and nectar of early flowers, such as willow catkins.

The queen bee is the first you will see. On emerging from hibernation, she feeds of nectar and pollen and searches for a suitable nest site to build up her colony. She stocks the nest with pollen and models a waxy rough cell around the pollen into which she lays a dozen eggs. The queen incubates the eggs by sitting on them while vibrating her flight muscles. The eggs hatch into larvae which are fed by the queen on nectar and pollen. The larvae pupate in a silk cocoon and the first adult worker bumblebees emerge from the pupae. The workers take over the responsibility of gathering pollen and nectar and the queen continues egg laying and cell building. In mid-summer, the queen starts laying female and male eggs. The females are fed extra food as they are the next generation of queens. The males and the new queens leave the nest to mate. Of the entire colony, only the new queens will survive. They find somewhere suitable to hibernate, and wake in early spring to start the cycle again.

To tell whether a bumblebee is male or female have a look at the antennae. Males have long, straight antennae and females have short antennae with a bend. The other giveaway is that males sit lazily on flowers and don't collect pollen. In contrast the females will be busily flying from flower to flower collecting pollen.

Don't be deceived by the Cuckoo Bumblebee. This cunning imposter was once like a bumblebee but has since switched to a parasitic existence. The females kill or evict the true queen bumblebee and use the workers to rear her own young.

For more information on what you can see at this time of year contact the |Countryside Team.