Bug FAQRusty-patched Bumble Bee
Bombus affinis · Order: Hymenoptera · Family: Apidae
Rusty-patched bumble bees are medium-large bumble bees native to eastern North America, now in decline. Queens are about 20 to 22 mm long, workers 10 to 16 mm, and males 13 to 17.5 mm; they nest underground in old rodent burrows. They have black hair on most of the abdomen, a rust-colored patch on the second segment, and a yellow-black “V” near the wing base.
Source: Wikipedia
How to recognize it
The abdomen is mostly black-haired except the two basal segments.
Source: Wikipedia
Size
Queens measure 20 to 22 mm in length and 9 to 11 mm in width. Workers are typically 10 to 16 mm long and 6 to 9 mm wide.
Source: Wikipedia
Where it lives
Nests are built underground, often in old rodent burrows. The species needs three nearby habitats for foraging, nesting, and hibernating.
Source: Wikipedia
What it eats
Feeds on nectar and pollen from many plants, such as Abelia grandiflora, Asclepias syriaca, and Linaria species.
Source: Wikipedia
Life cycle
Bumble bees are eusocial, living in colonies that can reach up to about 2,100 individuals in captivity, but are smaller in the wild.
Source: Wikipedia
When you see it
It was once common in southern Ontario until the 1980s, after which numbers have sharply declined.
Source: Wikipedia
Where it comes from
It is endemic to North America.
Source: Wikipedia
Where it is found in the US
Recorded in 36 of 51 states and DC. Most records: Minnesota, Wisconsin, Michigan, Illinois, Ohio, Iowa, New York, Connecticut.
Darker = more records. Counts are museum and citizen-science records, not population size.
Source: GBIF
Status: native in North America; native in Canada; native in United States. Source: iNaturalist
Months it is reported in the US
Source: GBIF
More photos
Questions people ask
How can I tell this bee apart from similar species?
Look for a rust-colored patch on the second abdominal segment and a yellow-black V near the wing base; other bumble bees lack this pattern.
Source: Wikipedia
Same family (Apidae)
Sources
- Wikipedia: https://en.wikipedia.org/wiki/Bombus_affinis
Look it up elsewhere: GBIF · iNaturalist · BugGuide · ITIS · Wikipedia
Text written 2026-10-22 from the sources above and checked sentence by sentence against them. Data fetched 2026-10-22.