Bumblebees More Helpful than Honeybees Newsletter

BUMBLEBEES – MORE HELPFUL THAN HONEYBEES
IN SOME WAYS

Bumblebees are among the most under appreciated of our beneficial insects. Most bumblebees are true natives and have coevolved with our native plants. They are great pollinators of native plants, a great variety of introduced ornamental plants and food crops. Bumblebees are more active in cooler weather and lower light levels than honeybees and are also adapted to different kinds of flowers. They are much better at pollinating tomatoes, peppers, squash, cucumbers, eggplants and blueberries because these plants require buzz pollination (sonication) where the pollen is dislodged by vibrating the flowers. Bumblebees are commercially available and managed as are honeybees, but they are more adapted for use in greenhouses to pollinate crops such as strawberries and tomatoes.

Bumblebees are fast workers. They visit twice as many flowers per minute as honeybees and because of their size, they carry relatively heavy loads which enables them to make long foraging trips. Due to their large size, they often achieve better contact with stamens and pistils than smaller insect pollinators.

And, bumblebees make few demands on their work conditions. They feel more at ease in greenhouses/tunnels than honeybees for instance. Even strong wind and drizzle will not keep them from doing their job.

One important advantage of bumblebees over honeybees is the absence of a communication system. Honeybees inform each other by means of the bees’ dance of the presence of an attractive food source outside the crop in which their pollination activities are required. As a result bees may leave collectively. Bumblebees do not have such a communication system. Should an individual bumblebee find an attractive food source elsewhere, it cannot inform its companions, so the other bumblebees continue to work in the present crop.

Another advantage of bumblebees over honeybees, especially in fruit crops, is that they are not so much tied to a specific area of the crop. They change trees more often and more easily than honeybees. This benefits the cross-pollination that is often required in fruit.

Bumblebees, like honey bees, are suffering declining numbers. Beginning in the 1990s researchers in the United States began to notice a decline in three common species of bumblebees. Their decline is likely due to a strain of fungus (Nosema bombi) introduced into the United States from Europe. Pesticides hurting their immune system is a part of the problem.

There is an inexpensive little book entitled The Natural History of Bumblebees by Kearns and Thomson (2001) that features a photographic field guide to North American species.