Bombus appositus
In 3 days ~10% in a week ~30%
Bombus appositus is a species of bumblebee known commonly as the white-shouldered bumblebee. It is native to western North America, including western Canada and the western United States. This species lives in open habitat, such as meadows and slopes. It nests underground or on the surface. Males congregate to seek mates. It feeds on a variety of plant taxa, including giant hyssops, thistles, gentians, owl's clovers, locoweeds, penstemons, and clovers. It especially favors subalpine larkspur (Delphinium barbeyi) and it serves as one of the plant's main pollinators.
This species has a range from southwestern Canada south to the Cascade Mountains and the Sierra Nevada, and west to central California. This species is a host to Bombus insularis, a species of cuckoo bumblebee. Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Grand Teton National Park | 🇺🇸 United States | |
| 2 | Rocky Mountain National Park | 🇺🇸 United States | |
| 3 | Glacier National Park | 🇺🇸 United States | |
| 4 | Olympic National Park | 🇺🇸 United States | |
| 5 | Banff National Park | 🇨🇦 Canada | |
| 6 | Yellowstone National Park | 🇺🇸 United States |
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Denver | 🇺🇸 United States |
Rare
Under 5% of wildlife watchers report a White-Shouldered Bumble Bee sighting in Yellowstone National Park on a given day, based on 8 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 127th most-seen of the 160 insects we can rate there. Over three days the chance rises to about 10%, and over a week to about 30%, if each day is a fresh chance.
July
In that month about 10% of wildlife watchers report a White-Shouldered Bumble Bee in Yellowstone National Park on a given day, against under 5% in August to June, the lowest months. That is one of Yellowstone National Park's driest months, with about 30 mm of rain against 70 mm in February.
Between noon and 3 pm
Across all the parks we cover, that three-hour window holds the most White-Shouldered Bumble Bee sightings with a recorded time, and about 9 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
6th of 6
Of the 6 parks where we can rate White-Shouldered Bumble Bee sightings, Yellowstone National Park ranks 6th at under 5%. The best odds are in Grand Teton National Park (United States, about 10%), Rocky Mountain National Park (United States, about 10%) and Glacier National Park (United States, about 10%).
Same genus: Bombus
The closest relatives of the White-Shouldered Bumble Bee that you can see in Yellowstone National Park (genus Bombus, Bumble Bees) are Vancouver Bumble Bee (about 10%), Red-Belted Bumble Bee (about 10%) and Nevada Bumble Bee (about 10%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the White-Shouldered Bumble Bee is recorded against all the insects logged in Yellowstone National Park (8 verified sightings from 2019 to 2026), calibrated against known sighting rates. Figures are rounded to the nearest 10% because citizen-science data supports honest approximations, not decimals, and months with records from fewer than five people show "—". How it works.
