Trott column: Rusty patched bumblebee becomes a household name
Endangered bee pollinates tomatoes and eggplants.
ALEXANDRIA — Many of the calls I receive during the growing season deal with insects. One you might not see, but should keep your eye out for, is the rusty patched bumble bee.
Dr. Elaine Evens, a University of Minnesota professor specializing in native and wild bee biology and bumble bee management, says that before the year 2000, the rusty patched bumblebee, Bombus affinis, was a common sight through most of Minnesota, across the east to the Atlantic Ocean and south through the Appalachian Mountains.
Suddenly, around the year 2000, they disappeared across their entire range. After 10 years of looking, conservationists and bumble bee biologists found rusty patched bumble bees again, primarily in and around urban centers in the Midwest, including the Twin Cities.
Though still here, current rusty patched populations are a shadow of their former selves, having lost over 95% of their range and experienced more than a 90% decrease in abundance. In 2017, the rusty patched bumblebee was granted endangered status by the U.S. Fish and Wildlife Service. In 2019, the rusty patched bumblebee was designated the Minnesota state bee.
How can you help the recovery of this endangered species?
You can help find rusty patched bumblebee locations to inform recovery efforts during the Great Backyard Bumblebee Count from July 24 to Aug. 2. Find a patch of flowers. Take photos of every bumble bee you see for 15 minutes. Share your findings with the Backyard Bumblebee Count on iNaturalist. More details here: backyardbbcount.wixsite.com/bumblebeecount.
Hopefully, working together, we can prevent extinction of this unique species. Here are some resources to learn more about rusty patched bumble bees: www.fws.gov/midwest/Endangered/insects/rpbb/.
Rusty patched bumble bees can be distinguished from other bumble bees by two features: A rusty patch in the middle of the second abdominal segment, and a T-shaped area of black hairs on the thorax. Males and workers have similar color patterns, but the queens have different coloration.
In 2018, a total of 471 rusty patched bumble bees were seen around the world, and165 of these were in Minnesota. This represents 35% of all documented rusty patched bumble bee individuals.
To learn more about rusty patched bumble bee identification visit these links:
Honey bees cannot pollinate eggplant and tomato flowers; bumblebees can. So, whenever you eat a tomato...thank a bumblebee. — April Pulley Sayre
Robin Trott is a horticulture educator with University of Minnesota Extension. Contact her at 320-762-3890, or at