Western Sheep Moth

Western Sheep Moth

Hemileuca eglanterina

Daily sighting probability ~20% · Possible
at Grand Teton National Park

In 3 days ~40% in a week ~80%

48 Verified sightings at Grand Teton National Park From 2019 to 2026
105 In all 5 parks
July Best month
☀️ Diurnal When it's spotted

About the Western Sheep Moth

The sheep moth, or common sheep moth (Hemileuca eglanterina), is a member of the family Saturniidae of silk moths and is native to western North America. In California, its range is west of the Sierran crest and the mountains of Southern California, ranging near to the coast. The moth is dayflying and appears in summer. It feeds on plants of three genera: Ceanothus, Rhamnus (including coffeeberry), and Rosa. Nuttall's sheep moth and one other species are similar, occurring in sagebrush areas east of the Sierra Nevada. The species was first described by Jean Baptiste Boisduval in 1852.

The sheep moth has a 5.5-8.5 centimeter wingspan and a relatively slender body. Its forewings are pink with a yellow streak in the middle and the hindwings are yellowish with variable black markings. There is an all-black form near Mount Shasta. The larvae are black with branched yellowish spines that become orange in later development and an orange-brown head. Wikipedia →

Global Distribution

Parks Where Found

# Park Country Daily sighting probability
1 Grand Teton National Park 🇺🇸 United States
~20%
2 Glacier National Park 🇺🇸 United States
~10%
3 Yosemite National Park 🇺🇸 United States
~10%
4 Olympic National Park 🇺🇸 United States
~10%
5 Yellowstone National Park 🇺🇸 United States
~10%

Before you go

What are the chances of seeing a Western Sheep Moth in Grand Teton National Park?

Possible

About 20% of wildlife watchers report a Western Sheep Moth sighting in Grand Teton National Park on a given day, based on 48 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 13th most-seen of the 140 insects we can rate there. Over three days the chance rises to about 40%, and over a week to about 80%, if each day is a fresh chance.

When is the best time to see a Western Sheep Moth in Grand Teton National Park?

July

In that month about 30% of wildlife watchers report a Western Sheep Moth in Grand Teton National Park on a given day, against under 5% in October to May, the lowest months. That is one of Grand Teton National Park's driest months, with about 20 mm of rain against 85 mm in December.

What time of day is best to see a Western Sheep Moth?

Between 1 and 4 pm

Across all the parks we cover, that three-hour window holds the most Western Sheep Moth sightings with a recorded time, and nearly all of them come between 6 am and 6 pm: it is a daytime animal.

Is Grand Teton National Park the best place to see a Western Sheep Moth?

Yes

Of the 5 parks where we can rate Western Sheep Moth sightings, Grand Teton National Park has the highest daily chance: about 20%. Next come Glacier National Park (United States, about 10%) and Yosemite National Park (United States, about 10%).

Where does the Western Sheep Moth sighting chance come from?

GBIF citizen-science records

It is estimated from how often the Western Sheep Moth is recorded against all the insects logged in Grand Teton National Park (48 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.

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