Orgyia leucostigma
In 3 days ~20% in a week ~30%
Orgyia leucostigma, the white-marked tussock moth, is a moth in the family Erebidae. The species was first described by James Edward Smith in 1797. The caterpillar is very common especially in late summer in eastern North America, extending as far west as Texas, California, and Alberta.
The genus name Orgyia is from the ancient Greek word ὄργυια, órgyia - 'outstretched arms'. So named because, when at rest, the moth stretches forward its forelegs like arms. Two or more generations occur per year in eastern North America. They overwinter in the egg stage.
Eggs are laid in a single mass over the cocoon of the female, and covered in a froth. Up to 300 eggs are laid at a time. The larvae are brightly colored, with tufts of hair-like setae. The head is bright red and the body has yellow or white stripes, with a black stripe along the middle of the back. Bright red defensive glands are seen on the hind end of the back. Four white toothbrush-like tufts stand out from the back, and a gray-brown hair pencil is at the hind end. The four white tufts on the larva's back may mimic the cocoons of parasitic wasps. Touching the hairs sets off... Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Gros Morne National Park | 🇨🇦 Canada | |
| 2 | Congaree National Park | 🇺🇸 United States | |
| 3 | Point Pelee National Park | 🇨🇦 Canada | |
| 4 | Acadia National Park | 🇺🇸 United States | |
| 5 | Shenandoah National Park | 🇺🇸 United States | |
| 6 | Riding Mountain National Park | 🇨🇦 Canada | |
| 7 | Great Smoky Mountains National Park | 🇺🇸 United States |
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Chicago | 🇺🇸 United States | |
| 2 | Minneapolis [Saint Paul] | 🇺🇸 United States | |
| 3 | Baltimore | 🇺🇸 United States | |
| 4 | Toronto | 🇨🇦 Canada | |
| 5 | Washington | 🇺🇸 United States | |
| 6 | Detroit | 🇺🇸 United States | |
| 7 | Montreal | 🇨🇦 Canada | |
| 8 | Dallas | 🇺🇸 United States | |
| 9 | Philadelphia | 🇺🇸 United States | |
| 10 | New York City | 🇺🇸 United States |
With luck
About 10% of wildlife watchers report a White-Marked Tussock Moth sighting in Baltimore on a given day, based on 26 verified sightings from GBIF citizen-science data. It is the 192nd most-seen of the 705 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.
June and August–November
In those months about 10% of wildlife watchers report a White-Marked Tussock Moth in Baltimore on a given day, against under 5% in July and December–May, the lowest months.
Between 8 and 11 am
Across all the parks we cover, that three-hour window holds the most White-Marked 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.
Among the best
Of the 10 cities where we can rate White-Marked Tussock Moth sightings, Baltimore ranks 3rd at about 10%, level with the leaders once rounded. The best odds are in Chicago (United States, about 10%) and Minneapolis [Saint Paul] (United States, about 10%).
Same family: Erebidae
The closest relatives of the White-Marked Tussock Moth that you can see in Baltimore (family Erebidae, Underwing, Tiger, Tussock, and Allied Moths) are Green Cloverworm Moth (about 10%), Isabella Tiger Moth (about 10%) and Fall Webworm Moth (about 10%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the White-Marked Tussock Moth is recorded against all the insects logged in Baltimore (26 verified sightings), 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.
