Erynnis tristis
In 3 days ~20% in a week ~40%
Erynnis tristis, commonly known as the mournful duskywing, is a species of spread-wing skipper in the butterfly family Hesperiidae that is commonly found in North America in oak woodlands. It is mottled brown with a white fringe on the hind wings. It is commonly mistaken for Erynnis funeralis due to both species having a white fringe on the hindwing. Erynnis tristis relies heavily on a variety of oak species as a hostplant, where the larvae feed on oak while the adults nectar from a variety of wild and garden flowers. This butterfly mates through hill-topping, where males perch on various objects to attract females.
The spherical eggs are laid on the terminal end of a hostplant. While initially yellow, the eggs will turn deep orange with maturation. Rather than being laid in clusters or groups, females will lay their eggs singly in separate locations. Once the egg progresses to the larval stage, the larvae are gray-green, covered with white spots throughout its body, and has lateral yellow stripes. The head has a brown coloration. The pupa are gray-green and are hairy.
The majority of the vestiture on the wings of the adults consists of primarily a brown coloration... Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Big Bend National Park | 🇺🇸 United States | |
| 2 | Channel Islands National Park | 🇺🇸 United States | |
| 3 | Cumbres de Monterrey National Park | 🇲🇽 Mexico | |
| 4 | Sequoia and Kings Canyon National Parks | 🇺🇸 United States |
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Sacramento | 🇺🇸 United States | |
| 2 | Los Angeles | 🇺🇸 United States | |
| 3 | Monterrey | 🇲🇽 México | |
| 4 | San Francisco | 🇺🇸 United States | |
| 5 | San Diego | 🇺🇸 United States | |
| 6 | San Antonio | 🇺🇸 United States | |
| 7 | Mexico City | 🇲🇽 México |
With luck
About 10% of wildlife watchers report a Mournful Duskywing sighting in Sequoia and Kings Canyon National Parks on a given day, based on 5 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 137th most-seen of the 161 insects we can rate there. Over three days the chance rises to about 20%, and over a week to about 40%, if each day is a fresh chance.
June–August and October
In those months about 10% of wildlife watchers report a Mournful Duskywing in Sequoia and Kings Canyon National Parks on a given day, against under 5% in September and November–May, the lowest months. Those are among Sequoia and Kings Canyon National Parks's driest months, with about 25 mm of rain a month against 190 mm in January.
Between 10 am and 1 pm
Across all the parks we cover, that three-hour window holds the most Mournful Duskywing sightings with a recorded time, and nearly all of them come between 6 am and 6 pm: it is a daytime animal.
Among the best
Of the 4 parks where we can rate Mournful Duskywing sightings, Sequoia and Kings Canyon National Parks ranks 4th at about 10%, level with the leaders once rounded. The best odds are in Big Bend National Park (United States, about 10%), Channel Islands 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 Mournful Duskywing is recorded against all the insects logged in Sequoia and Kings Canyon National Parks (5 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.
