Western Bumble Bee

Western Bumble Bee

Bombus occidentalis

Daily sighting probability ~10% · With luck
at Olympic National Park

In 3 days ~20% in a week ~30%

13 Verified sightings at Olympic National Park From 2019 to 2026
129 In all 6 parks
August Best month
☀️ Diurnal When it's spotted

About the Western Bumble Bee

Bombus occidentalis, the western bumble bee, is one of around 30 bumble bee species present in the western United States and western Canada. A recent review of all of its close relatives worldwide appears to have confirmed its status as a separate species.

Western bumble bee workers have three main color variations. The first color variation is found from northern California, north to British Columbia, and east to southwest Saskatchewan and Montana. B. occidentalis in these areas have yellow hair on front part of thorax. They are also marked by black hair segments on the basal section of the fourth abdominal segments have black hair and whitish lower edge of the fourth and fifth abdominal segments. In addition, they also have sparse whitish hairs that may appear black on the sixth abdominal segment, and an entirely black head.

The second color variation is found along the central coast in California. It has yellow hair on the sides of the second abdominal segment and all of the third abdominal segment and a reddish-brown hair on fifth abdominal segment.

The third color variation is found from the Rocky Mountains to Alaska. It has yellow hair on the thorax behind the... Wikipedia →

Global Distribution

Parks Where Found

# Park Country Daily sighting probability
1 Grand Teton National Park 🇺🇸 United States
~10%
2 Glacier National Park 🇺🇸 United States
~10%
3 Great Bear Rainforest 🇨🇦 Canada
~10%
4 Yellowstone National Park 🇺🇸 United States
~10%
5 Olympic National Park 🇺🇸 United States
~10%
6 Rocky Mountain National Park 🇺🇸 United States
<5%

Cities Where Found

# City Country Daily sighting probability
1 Calgary 🇨🇦 Canada
~10%
2 Denver 🇺🇸 United States
<5%

Before you go

What are the chances of seeing a Western Bumble Bee in Olympic National Park?

With luck

About 10% of wildlife watchers report a Western Bumble Bee sighting in Olympic National Park on a given day, based on 13 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 94th most-seen of the 207 insects we can rate there. Over three days the chance rises to about 20%, and over a week to about 30%, if each day is a fresh chance.

When is the best time to see a Western Bumble Bee in Olympic National Park?

June to August

In those months about 10% of wildlife watchers report a Western Bumble Bee in Olympic National Park on a given day, against under 5% in September to May, the lowest months. Those are among Olympic National Park's driest months, with about 55 mm of rain a month against 370 mm in November.

What time of day is best to see a Western Bumble Bee?

Between 11 am and 2 pm

Across all the parks we cover, that three-hour window holds the most Western 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.

Is Olympic National Park the best place to see a Western Bumble Bee?

Among the best

Of the 6 parks where we can rate Western Bumble Bee sightings, Olympic National Park ranks 5th at about 10%, level with the leaders once rounded. The best odds are in Grand Teton National Park (United States, about 10%), Glacier National Park (United States, about 10%) and Great Bear Rainforest (Canada, about 10%).

Where does the Western Bumble Bee sighting chance come from?

GBIF citizen-science records

It is estimated from how often the Western Bumble Bee is recorded against all the insects logged in Olympic National Park (13 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.

← Back to Olympic National Park