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Bumble Bees in Ohio: Natural History and Identification of Common Species

Agriculture and Natural Resources
Denise Ellsworth, Program Director, Entomology, Ohio State University Extension

A bumble bee flying from flower to flower is a common sight in the summer landscape. These large, fuzzy bees are sometimes called the teddy bears of the bee world because of their hairy bodies and bumbling flight patterns. North America is home to 45 species of native bumble bees, with about a dozen species seen in Ohio. These bees play an important role as pollinators of crops and wild plants.

Bumble bee on yellow flowerForaging bumble bee worker. Photo by David Cappaert,

Bumble bees are sometimes confused with carpenter bees, particularly in the spring when both species are active and of a similar size. Bumble bees have hairy abdomens and heart-shaped faces, while carpenter bees have shiny abdomens and wide, round faces. Bumble bees do not nest in wood, bore holes in wood structures, or hover menacingly as do male carpenter bees near nesting sites.

Bumble bees are social bees that live together in a colony. Each colony is active for only one year, with new colonies started each spring by a new queen bumble bee. This differs from honey bees, which have a perennial colony that survives from year to year.

Nest of bumble beesBumble bee nest. Photo by MaLisa Spring Old nest removed from chickadee nest boxBumble bee nest removed from chickadee nest box. Photo by Sharon Grossman.

In early spring, each overwintering bumble bee queen must find a suitable home for her colony, commonly in an abandoned rodent burrow or sometimes directly on the ground, depending on the species. Sometimes, bumble bees will nest in unused straw or hay bales, unturned compost piles, upside down clay pots, at the base of bunch grasses, in bird houses or feeders, or in crevices in rock walls.

Bumble bee on blueberry plant close-up of female bee corbicula Bumble bee on yellow flower with full corbicula

Queen bumble bee in blueberry field in spring. Photo by Denny Reiser.

Female bumble bee’s corbicula on the hind leg. Photo by Allan Smith-Pardo.

Worker bumble bee with a corbicula full of pollen. Photo by @jeffnoh,

Once she finds a nesting site, the queen secretes wax to create comb and then lays about a dozen eggs. She mated with a drone last fall, and has reserved the sperm in a special organ in her abdomen. Using the heat generated by vibrating her flight muscles, the queen keeps the eggs warm. When the larvae hatch, they eat pollen and nectar that the queen has collected. The queen continues to keep the nest warm and collect food for the developing larvae. About two weeks later, the larvae pupate, then emerge in about another two weeks as adult workers.

Worker bees, all females, are much smaller than the queen, particularly early in the season. They take over the work of tending and guarding the nest and bringing pollen and nectar back to the colony. Female bumble bees transport pollen on a flattened section on their hind legs called the corbicula.

The queen continues to lay batches of eggs throughout the summer, rarely leaving the nest. Toward the end of summer, the queen lays unfertilized eggs that will become male drones, and other fertilized eggs that will be reared as new queens. The new queens and drones leave the colony to mate with other bumble bees of the same species. In most species, queen bumble bees will only mate once.

Bumble bees gather on goldenrod Queen bumble bee on a scrap of paper between two fingers One female and two drones on green leaves

Bumble bee drones congregating on goldenrod. Notice the males’ yellow mustaches. Photo by Steve Upperman.

Queen bumble bee. Photo by Denise Ellsworth.

Bumble bee queen with two drones attempting to mate; only one will succeed. Photo by Denny Reiser.

Newly mated queens feed on flowers to pack their bodies full of fat to survive the winter. Each queen will spend the winter burrowed about 10 inches below ground, emerging in spring to start a new colony. All the members of the old colony die with the winter’s cold, including the old queen, and all workers and drones.

Unlike many other bees, bumble bees can forage for food in cool, wet conditions and in low light. This makes them important pollinators of plants that bloom in early spring or grow in shady conditions. Their robust bodies help them fly far from the nest in search of food—sometimes more than a mile if food is scarce.

Bumble bees are key pollinators of crops such as apples, cucumbers, squash, raspberries, blueberries, and greenhouse tomatoes. They are also essential pollinators of many native plants, and in some cases serve as the only pollinator able to pollinate certain native plants.

Bumble bees can do something only a few other species of bee can: an action called buzz pollination. Blueberries, cranberries, tomatoes, and peppers are some of the plants that require buzz pollination to release pollen. In buzz pollination, the worker bee wraps her legs around the flower and vibrates her wing muscles without moving her wings. This creates a “buzz” that is musically similar to the tone of a middle C. The vibration shakes the pollen-holding anther, releasing the flower’s pollen like a salt-shaker releasing salt.

Bumble bees rarely sting when foraging for food, but can and will sting repeatedly to protect the nest. People are often stung when unknowingly walking near or stepping onto a bumble bee nest. Bumble bees do not have barbed stings like honey bees do, and so can sting repeatedly.

About a dozen species of bumble bees live in Ohio. According to the Ohio Bee Atlas, a citizen science project on the iNaturalist platform (, the following are the nine most commonly observed bumble bee species by citizen scientists in 2017 and 2018, from most to least commonly observed:

Pink impatiens flower with bumble bee center Bumble bee on orange flower Bumble bee on white flower with faint yellow "w" on black abdomen

Common eastern bumble bee. Photo by Steve Upperman.

Brown-belted bumble bee. Photo by Susan Moore.

Two-spotted bumble bee; note faint yellow “w” on the otherwise black part of the abdomen. Photo by Karen Goodell.

  1. Common Eastern bumble bee (Bombus impatiens)
  2. Brown-belted bumble bee (Bombus griseocollis)
  3. Two-spotted bumble bee (Bombus bimaculatus)
  4. Golden northern bumble bee (Bombus fervidus)
  5. Perplexing bumble bee (Bombus perplexus)
  6. Half-black bumble bee (Bombus vagans)
  7. Black-and-gold bumble bee (Bombus auricomus)
  8. American bumble bee (Bombus pensylvanicus)
  9. Lemon cuckoo bumble bee (Bombus citrinus)

Several species of Ohio bumble bees that used to be common are becoming much less so, such as golden northern bumble bee, black-and-gold bumble bee and the American bumble bee. The rusty-patched bumble bee (Bombus affinis) was listed as a federally endangered species in 2017 and has only rarely been spotted in Ohio in the last two decades.

Bumble bee with rusty red patch mid-abdomenThe endangered rusty patched bumble bee. Photo by USGS bee inventory and monitoring lab.

Bumble bees face many of the same threats facing honey bees and other pollinators, including lack of flowers, decrease in nesting habitat, and poisoning from pesticides. Bumble bees are also impacted by diseases that only infect bumble bees, and are thought to be particularly vulnerable to changes in climate

To conserve bumble bees, gardeners and land managers of any scale can protect potential and actual nesting sites, provide flowers that bumble bees prefer, and decrease or eliminate pesticide use.

A few flowers bumble bees prefer:

Trees: black locust, cherry, crab apple, redbud, willow, redbud

Native perennials: aster, goldenrod, ironweed, monarda, purple coneflower

Weeds: birdsfoot trefoil, chickory, red clover, teasel, white clover

Bumble bee queen clinging to white and pink flowers Purple, skinny petal flower with bumble been center  Bumble bee on spiky flower with little purple petals

Bumble bee queen on crabapple flower. Photo by Denise Ellsworth.

Bumble bee on aster. Photo by Amy Schnebelin.

Brown-belted bumble bee on teasel. Photo by Denny Reiser.

For more information:

Bumble Bee keys including Ohio:

Bumble Bees of the Eastern United States (free PDF guide) by Sheila Colla, Leif Richardson, and Paul Williams:

Ohio Bee Atlas:

Bumble Bee Conservation, The Xerces Society:

Program Area(s):




Source:  ODNR




Source:  OSU Extension




Bumblebees Face Extinction From the Climate Crisis

A bumblebee on a Dusky Cranesbill geranium plant on May 14, 2018 in London, England. Victoria Jones – WPA Pool / Getty Images

Rampant pesticide use and habitat loss has already crippled bumblebee populations. New research now shows that warming temperatures around the world will further push bumblebees to the brink of extinction, as The New York Times reported.

The loss of bumblebees spells trouble for plant biodiversity since they are some of the most important pollinators in the world. Bumblebees pollinate and fertilize a wide array of plants and crops, including tomatoes, blueberries and squash. However, if you are in North America, you are nearly 50 percent less likely to see a bumblebee in any given area than you were prior to 1974, according to the new research, as National Geographic reported.

The new research, published in the journal Science, employed a massive dataset and a complex modeling system to look at bee populations and to find the reason for their decline. The researchers found that bee populations have experienced the largest decline in places that have warmed at a faster rate than the rest of the planet.

Some bumblebee species have disappeared from areas where they once flourished. For example, the rusty-patched bumblebee once thrived in Ontario, but now it is no longer found in Canada. In the U.S., it is endangered, as National Geographic reported.

“The things [we] grew up with as kids are fading away very fast,” said Dr. Jeremy Kerr, senior author of the study and a biology professor at the University of Ottawa, as CNN reported.

“It’s not just that we’re looking at what our kids will experience; it’s that we are looking back not even a full generation, just to when we were kids, and saying, ‘Could we take our children to places we loved and find what we found?’ What our study says is that that answer is no across entire continents.”

The scientists at the University of Ottawa looked at 66 different bumblebee species across two continents. They found that bumblebee populations have declined by 46 percent in North America and by 17 percent in Europe compared to the period from 1901 to 1974, according to the study.

“The scale of this decline is really worrying,” said Peter Soroye, a doctoral student in biology at the University of Ottawa and lead author of the study, to The New York Times. “This group of organisms is such a critical pollinator in wild landscapes and agricultural regions.”

To build their model, the researchers relied on a database of roughly 550,000 bee records over a century. The researchers looked at two time periods: 1901 to 1974 and 2000 to 2015. Then they examined if temperatures and precipitation exceeded the bumblebees’ tolerance level, as CNN reported.

Bumblebees, which prefer cooler, slightly wet temperatures, perished in areas that had heat waves, prolonged dryness, or frequently extreme weather. That pattern, which is commensurate with the climate crisis, threatens bumblebees with extinction and from the possibility of establishing colonies or creating new species, according to CNN.

Kerr said that there are several mechanisms at play. Bees can simply overheat. Or, as plants wither, the bees starve. Additionally, early springs and re-freezings threaten queens, which spend the winter in forest leaf litter, as National Geographic reported.

The loss of bees may have a devastating effect on plants that rely on them and animals that rely on those plants.

“As these plants are then used by myriad other organisms, the decline of bumblebees can have cascading ecological [effects] that may collectively cause biodiversity loss,” said Matthew Austin, a Ph.D. student and researcher at the University of Missouri in St. Louis who wasn’t involved in the paper, to National Geographic.

“Our results show that we face a future with many less bumble bees and much less diversity, both in the outdoors and on our plates,” said Soroye in a University of Ottawa statement.

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