Halysidota harrisii
In 3 days ~40% in a week ~70%
Halysidota harrisii, the sycamore tiger moth, is a moth belonging to the family Erebidae and the tribe Arctiini, the tiger moths. The species was first described by Benjamin Dann Walsh in 1864. It is found in southeastern Canada, the eastern parts of the United States, and northeastern Mexico.
The larvae have yellow-orange heads and bodies covered with hair, and they can grow to approximately 25–35 mm in length. They exhibit two pairs of long, orange hair-pencils and two pairs of white hair-pencils towards the front of their body. They also exhibit one pair of white hair-pencils near the back of their body.
The adults are pale yellow with dark bands on the forewings. Each forewing is 24–26 mm in length, making the wingspan approximately 50 mm. As adults, they are almost indistinguishable from the closely related Halysidota tesselaris.
The sycamore tiger moth produces two generations each year. Moths emerge from overwintering cocoons from May to June. After mating, they lay egg masses on bark and the underside of leaves. The larvae feed on the American sycamore tree, Platanus occidentalis. They pupate in late June and July, and emerge as moths in July... Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Great Smoky Mountains National Park | 🇺🇸 United States | |
| 2 | Shenandoah National Park | 🇺🇸 United States | |
| 3 | Cumbres de Monterrey National Park | 🇲🇽 Mexico |
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Detroit | 🇺🇸 United States | |
| 2 | Baltimore | 🇺🇸 United States | |
| 3 | Philadelphia | 🇺🇸 United States | |
| 4 | New York City | 🇺🇸 United States | |
| 5 | Washington | 🇺🇸 United States | |
| 6 | Chicago | 🇺🇸 United States | |
| 7 | Boston | 🇺🇸 United States | |
| 8 | Houston | 🇺🇸 United States | |
| 9 | Monterrey | 🇲🇽 México | |
| 10 | Austin | 🇺🇸 United States |
Possible
About 20% of wildlife watchers report a Sycamore Tussock Moth sighting in Great Smoky Mountains National Park on a given day, based on 82 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 58th most-seen of the 822 insects we can rate there. Over three days the chance rises to about 40%, and over a week to about 70%, if each day is a fresh chance.
August and September
In those months about 30% of wildlife watchers report a Sycamore Tussock Moth in Great Smoky Mountains National Park on a given day, against under 5% in November to May, the lowest months.
Between 11 am and 2 pm
Across all the parks we cover, that three-hour window holds the most Sycamore Tussock Moth sightings with a recorded time, and about 9 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
Yes
Of the 3 parks where we can rate Sycamore Tussock Moth sightings, Great Smoky Mountains National Park has the highest daily chance: about 20%. Next come Shenandoah National Park (United States, about 10%) and Cumbres de Monterrey National Park (Mexico, about 10%).
GBIF citizen-science records
It is estimated from how often the Sycamore Tussock Moth is recorded against all the insects logged in Great Smoky Mountains National Park (82 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.
