Most people know that bees are one of the most important pollinators of not just our pretty flowers, but also many of our important food crops. You are probably picturing a cute little honeybee perched on the edge of a blossom right now, and you would probably be surprised to learn that it’s not the little honeybee that is the best at pollination but rather the big ole bumble bee!
How is that so? Instead of picking single grains of pollen at a time, a bumble bee uses a method called “buzz pollination,” during which it lands on a flower and vibrates its wings so rapidly that the buzzing sound is produced. The vibration causes the pollen from several of the stalks (anthers) in the middle of the flower to fall on the bee’s body. Covered with the little grains, the bee then grooms itself, mixing the pollen with the flower’s nectar and saliva, forming a sticky substance that it transfers to structures on its legs called pollen baskets.
Although this is a very efficient method of obtaining pollen, the bee still visits several flowers before heading back to its colony to store its bounty for feeding young, and in doing so, carries out the pollination that is so vital to floriculture and agriculture.
The most common bumble bee species in Connecticut is the common eastern, first noted here in 1863. Four other species located here are the half-black, perplexing, brown-belted and two-spotted. All these species form underground nests, usually located near woodlands or under dense brush. There are 10 other species that have been recorded in our state, but they are declining, rare or threatened, most often because of pesticides and insecticide use.
Getting back to those busy queen bumbles, they are crucial to the success of any colony. They are the ones that select an appropriate site for the nest. After choosing a place, they make little wax “pots” to fill with nectar from flowers that they visit so they will have something to drink when it’s too hot to forage. They also make wax brood cells that they fill with pollen and nectar and lay their eggs on the top of these cells.
In four to five weeks, the eggs hatch. The larvae all grow into female workers that will take over the chores of getting pollen and cleaning and guarding the nest, freeing the queen to concentrate on laying more eggs. In late summer, the eggs will finally begin to produce male larvae, and occasional new queens that will go off to other colonies and mate with the males there. The new queens, now full of eggs, will hibernate for the winter while the old queens, workers and the males of the original colony die. A bumble bee colony lives for only one year, whereas a honey bee colony survives for many years, until a natural disaster such as severe weather, a human or a bear dismantles it. A bumble bee colony will have a few hundred bees, while a honey bee colony can have as many as 80,000.
In closing, I can relate a fun story about hibernating bumble bees. My favorite young man was helping me with late fall clean-up. I heard a shout and looked up to see him jumping back from the spot he was raking near the entrance to my woods. I asked him what was wrong; he replied, “BEES!” He had uncovered a nest of hibernating bumbles. Not being able to reconstruct the nest, and knowing the bees were unconscious (or even dead) on that cold morning, I carefully picked them up one by one and deposited them in a new nest I made under the forsythia patch. He couldn’t quite muster up the courage to hold one, but it was a “teachable moment” and I got some solid props.
If you’d like to learn even more about bumble bees, visit the Connecticut Bumble Bee Guide online.