Strymon acadica
In 3 days ~30% in a week ~50%
Satyrium acadica, the Acadian hairstreak, is a butterfly of the family Lycaenidae. It is found in North America from British Columbia east to Nova Scotia and south to Idaho, Colorado, the northern Midwest, Maryland, and New Jersey.
The wingspan is 29–38 mm. Like other hairstreaks, each hindwing has two tails near the tip. The shorter, upper tail is very short and often does not look at all like a tail. The upperside is brown grey, while the underside of the hindwings is grey. Adults are on wing from June to August in one generation per year. They feed on flower nectar of various flowers such as butterflyweed, milkweeds, and thistles.
The larvae feed on the leaves of Salix species, including S. nigra and S. sericea. The species overwinters as an egg. Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Yosemite National Park | 🇺🇸 United States |
More parks will be added in future updates.
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Toronto | 🇨🇦 Canada | |
| 2 | Sacramento | 🇺🇸 United States | |
| 3 | Chicago | 🇺🇸 United States | |
| 4 | San Francisco | 🇺🇸 United States |
With luck
About 10% of wildlife watchers report a Strymon acadica sighting in Yosemite National Park on a given day, based on 32 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 51st most-seen of the 227 insects we can rate there. Over three days the chance rises to about 30%, and over a week to about 50%, if each day is a fresh chance.
June
In that month about 20% of wildlife watchers report a Strymon acadica in Yosemite National Park on a given day, against under 5% in August to May, the lowest months. That is one of Yosemite National Park's driest months, with about 25 mm of rain against 220 mm in January.
Between 10 am and 1 pm
Across all the parks we cover, that three-hour window holds the most Strymon acadica sightings with a recorded time, and about 9 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
Only Yosemite National Park, in our data
Yosemite National Park is the only park on Wallace's Line with enough records to rate Strymon acadica sightings: about 10% of wildlife watchers there report one on a given day.
Same genus: Strymon
The closest relatives of the Strymon acadica that you can see in Yosemite National Park (genus Strymon, Scrub-Hairstreaks) are Gray Hairstreak (about 10%) and Strymon saepium (about 10%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Strymon acadica is recorded against all the insects logged in Yosemite National Park (32 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.
