The word “bumblebee” brings up many topics. There is the current Transformers movie that features an Autobot scout named Bumblebee who transforms into a Volkswagen beetle. There are also the teddy-bear cute insects that grace the covers of numerous children’s books. Then the are the real McCoy, the 250 or so species of the Bombus genus – the bumblebees, also known as “humble-bees.”
The name bumblebee is derived from "bumble," meaning to buzz or move about randomly and “bee.” Even Charles Darwin in his On the Origin of the Species referred to these pollinators as “humble-bees,” however, after World War II the term humble-bee was replaced by the present “bumblebee.”
No matter their name, bumblebees share the Bombini tribe with honeybees, orchard bees, and stingless bees. All four groups are lumped together as corbiculate bees, meaning those with pollen baskets. No, not the kid’s book version of wicker baskets held over their leg, but rather a polished cavity on the hind leg that is surrounded by hairs, called a corbicula. Think “saddlebag” where queens and worker bees stuff pollen they’ve collected. Male bees don't have this corbicula structure.
It is no wonder bumblebees make the cute and fuzzy list. They’re plump and hairy and have large, colorful bands or sleek black bands that help distinguish the species. They are almost like flying bears, like Baloo from the Jungle Book, and who doesn’t like bears!
They Don't Want to Sting You
Even the females, who have stingers, will rarely sting humans unless provoked or handled. If you are unlucky enough to suffer a bumbleebee sting don't panic. The pain is unpleasant but is ultimately tolerable and not nearly as intense as the pain you can experience from having a run in other stingers like wasps. Barring a very poor reaction such as an allergy being triggered, the swelling and pain from one of their stings usually presents and subsides all in the course of 90 minutes or so. Humble to a fault, those bees.
Bumblebees vs. Honey Bees
Like their cousins the honeybees, bumblebees are proficient and important pollinators. They don’t get the attention honey bees do because they are more selective pollinators or are not found in large enough numbers to be efficient on large-scale agricultural sites. They do, however, have their perks.
Bumblebees make a bigger impact in terms of pollinating native plants than honey bees. Because of their large size, these bees warm up earlier in the day and can stay out later than the slenderer honey bees. Their specialized “buzz pollination” benefits certain agricultural species such as blueberries, tomatoes, and squash plants more so than honey bees.
Buzz pollination is when a bumblebee latches onto a specialized flower’s anthers with its teeth and wraps its legs around the anthers. They then use their muscles to vibrate their whole bodies, not just their wings, which shakes loose the pollen from within the anther sac. The bee then grooms itself and stores the pollen in its corbicula. This specialized type of pollination allows the bumblebee to visit certain flowers almost exclusively and not have to compete with other pollinators.
Their importance as pollinators, helping a billions of dollars agriculture business, gives them a seat at the table. With recent declines in European honeybee colonies collapsing, the importance of native bees grows larger. Unfortunately, several bumblebees have already gone extinct in North America and others have disappeared over large portions of their former ranges. The culprit might surprise you.
Many experts in the field believe, although have not proven, that unregulated trade is one of the primary reasons behind the decline. In the early 1990s, bumblebee queens were sent to Europe to form colonies for the agricultural industry in the U.S., the colonies that were shipped back carried with them a parasitic fungus that wiped out native bees exposed to the fungus. The native bees had no defense against the fungus.
The U.S. Department of Agriculture suspended bumblebee shipments between Europe and the United States in 1994.That has not stopped the domestic trade or demand for bumblebees which pollinate greenhouse tomatoes, peppers, and berries, introducing species into new ranges which may have had consequences for native populations. Although petitioned to regulate the domestic trade to protect all species, that action has not yet been accepted.
Other Factors Affecting Bumblebees
Habitat loss, pesticides, competition from honeybees, and climate change are other factors that threaten bumblebees. Some farmers have planted borders of native wildflowers near their farms to provide for and encourage bumblebees. They are using the lowest-toxic pesticide or insecticide and targeting the problem directly, not broadly applying the pesticides. One issue with pesticide use is often too much is applied, so follow the label directions. Unlike many native bees, bumblebees live in small colonies, so providing adequate nesting sites is also important. These may be on the ground, in compost piles, brush piles, and other sites that provide protection for the colony.
Contribute to Citizen Science
In addition to planting and protecting habitat to encourage bumblebees, there are other ways to contribute to the understanding of these creatures. Citizen-science projects such as The Great Sunflower Project or Bumble Bee Watch, sponsored by the Xerces Society and other organizations, is a great way to learn more about these bees while providing data to researchers who are working on a larger scale.
The Great Sunflower Project investigates pollinators, not just bumblebees, that visit annual sunflowers and other plants. Gardeners grow Lemon Queen Sunflowers or observe pollinators on any local flowering plants, and report the data. Gardeners with fruit trees, berry bushes, tomatoes, and other crops need to have bees show up and do their “pollination thing.”
Bumble Bee Watch is a project that looks more closely at bumblebees. Citizen scientists sign up for free, snap a cellphone or camera image of a bumblebee, attempt to determine the species, and upload the data through the website or app. Having many eyes watching for bumblebees increases the success of this project as researchers look to better understand the status of bumblebees in North America.
And, just think, as you’re gathering data, harvesting fruit, enjoying the garden, you can hum and dance like Baloo to “The Bare Necessities” across your yard.