Estigmene acrea
In 3 days ~10% in a week ~20%
Estigmene acrea, the salt marsh moth or acrea moth, is a moth in the family Erebidae. The species was first described by Dru Drury in 1773. It is found in North America, and southwards from Mexico to Colombia. The head and thorax are white, and the abdomen is yellow orange with a row of black spots. The forewing is white with a variable pattern of black spots, with some individuals lacking any spots. The hindwing is yellow orange in males and white in females. Both sexes have three or four black spots or blotches on the hindwings. The wingspan measures 4.5 to 6.8 cm (1.8 to 2.7 in).
This moth is generally seen from May to August, but it is seen all year in southern Florida and southern Texas. The yellowish eggs are laid in clusters on the host plant leaves. The larva, known as the salt marsh caterpillar, which grows to about 5 cm (2 in) in length, is highly variable in color, ranging from pale yellow to rusty orange brown to dark brownish black. It is hairy, with numerous soft setae, growing in tufts (several tufts on each segment), with a few individual hairs that are longer toward the end of the body. The thoracic and abdominal segments... Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Channel Islands National Park | 🇺🇸 United States | |
| 2 | Padre Island National Seashore | 🇺🇸 United States | |
| 3 | Shenandoah National Park | 🇺🇸 United States | |
| 4 | Congaree National Park | 🇺🇸 United States | |
| 5 | Point Pelee National Park | 🇨🇦 Canada | |
| 6 | Merritt Island National Wildlife Refuge | 🇺🇸 United States | |
| 7 | Everglades National Park | 🇺🇸 United States | |
| 8 | Cumbres de Monterrey National Park | 🇲🇽 Mexico |
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Austin | 🇺🇸 United States | |
| 2 | Houston | 🇺🇸 United States | |
| 3 | San Antonio | 🇺🇸 United States | |
| 4 | Dallas | 🇺🇸 United States | |
| 5 | San Diego | 🇺🇸 United States | |
| 6 | Los Angeles | 🇺🇸 United States | |
| 7 | Tijuana | 🇲🇽 México | |
| 8 | Monterrey | 🇲🇽 México | |
| 9 | Montreal | 🇨🇦 Canada | |
| 10 | Mexico City | 🇲🇽 México |
Rare
Under 5% of wildlife watchers report a Salt Marsh Moth sighting in San Francisco on a given day, based on 96 verified sightings from GBIF citizen-science data. It is the 156th most-seen of the 737 insects we can rate there. Over three days the chance rises to about 10%, and over a week to about 20%, if each day is a fresh chance.
September and October
In those months about 10% of wildlife watchers report a Salt Marsh Moth in San Francisco on a given day, against under 5% in November to August, the lowest months. Those are among San Francisco's driest months, with about 15 mm of rain a month against 110 mm in December.
Between 9 am and noon
Across all the parks we cover, that three-hour window holds the most Salt Marsh Moth sightings with a recorded time, and about 8 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
15th of 21
Of the 21 cities where we can rate Salt Marsh Moth sightings, San Francisco ranks 15th at under 5%. The best odds are in Austin (United States, about 20%), Houston (United States, about 20%) and San Antonio (United States, about 20%).
Same family: Erebidae
The closest relatives of the Salt Marsh Moth that you can see in San Francisco (family Erebidae, Underwing, Tiger, Tussock, and Allied Moths) are Spotted Tussock Moth (about 10%) and Western Tussock Moth (about 10%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Salt Marsh Moth is recorded against all the insects logged in San Francisco (96 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.
