Native Bee Roundup: Bumblebees
Most native bee species are solitary, meaning they do not form superorganism hives like the European honeybee. Some nest in the ground, in hollow stems, cavities, old wood, or old rodent nests. In general, these bees are hundreds of times better at pollinating than European honeybees, mostly because they have evolved specifically for the ecosystems in which they reside.
Because native bees are mostly solitary, it is often difficult to collect reliable data on them. We still have so much to learn about native bees, and more research is required to get a full understanding of these species. Over half of our data for our native species is deficient, and in most cases, we lack historical data and lack data on current populations.
Still, we can see general trends on native bee populations. Some native bees are thriving, but others are in severe decline, and other still we suspect are in decline. Native bee species are the most at risk for extinction.
Bumblebees are the only Michigan species that is truly social—meaning they also create hives, though much smaller than honeybees. But unlike honeybees, only mated queens survive the year and hibernate, emerging the next year to build their hives up again.
Bumble bees are able to fly in cooler temperatures and lower light levels than many other bees, and they perform a behavior called “buzz pollination,” in which the bee grabs the pollen producing structure of the flower in her jaws and vibrates her wing musculature causing vibrations that dislodge pollen that would have otherwise remained trapped in the flower’s anthers. Some plants, including tomatoes, peppers, and cranberries, require buzz pollination.
Yellow-banded Bumblebee (Bombus terrcola)
The yellow banded bumble bee is a highly social insect with a highly advanced level of social organization. They live in colonies which include a founding queen, sterile female worker bees, male bees and new queens. Yellow banded bumble bees are an important and especially effective pollinator of wildflowers and crops - many of which, birds and other animals, rely on for food.
Yellow banded bumble bees were once widely dispersed throughout the upper United States and Canada, but various stressors have resulted in a major range contraction and decrease in population numbers. The Yellow-banded Bumble Bee has not been seen in most parts of its range in the U.S. since 1999, with the exception of records in a few locations in Wisconsin in 2007 and a single location in Pennsylvania in 2006.
Numerous studies indicate that this species has declined, both regionally and locally, especially in the southern portion of its range. While its decline has not been as rapid and drastic as other native species, it did exhibit significant declines in relative abundance across its northeastern U.S. range.
Where these bees were once very common, they were nearly impossible to find. The Xerces Society for Invertebrate Conservation has put this species on their “red list” of endangered bees, though it remains unlisted on the US Fish and Wildlife designation.
Rusty-patched Bumblebee
Rusty patched bumble bees live in colonies that include a single queen and female workers. The colony produces males and new queens in late summer. Queens are the largest bees in the colony, and workers are the smallest. All rusty patched bumble bees have entirely black heads, but only workers and males have a rusty reddish patch centrally located on the back.
Historically, the rusty patched bumble bee was broadly distributed across the eastern United States, Upper Midwest, and southern Quebec and Ontario in Canada. Since 2000, this bumble bee has been reported from only 13 states and 1 Canadian province: Illinois, Indiana, Iowa, Maine, Maryland, Massachusetts, Minnesota, North Carolina, Ohio, Pennsylvania, Tennessee, Virginia, Wisconsin and Ontario, Canada.
It is estimated that this species has declined from an estimated 87% of its historic range in recent years.
It is the first bee to be listed as federally endangered by the US Fish and Wildlife Service in 2017.
Prior to its listing as endangered in 2017, the species experienced a widespread and steep decline. The US Fish and Wildlife Service finalized their recovery plan for the species in 2021, and is working to conserve this species.
