Lethe anthedon
In 3 days ~10% in a week ~20%
Lethe anthedon, the northern pearly-eye, is a species of butterfly in the subfamily Satyrinae of the family Nymphalidae. It is found in North America, from central Saskatchewan and eastern Nebraska east to Nova Scotia, south to central Alabama and Mississippi.
The wingspan is 1 1/2 to 2 1/2 inches (43–67 mm.) The upperside is brown with dark eyespots and the underside is brown. Adults feed on dung, fungi, carrion and sap from willows, poplars, and birches. The larvae feed on various grasses, including Leersia virginica, Erianthus species, Muhlenbergia species, bearded shortgrass (Brachyelytrum erectum), Chasmanthium latifolium, bottlebrush grass (Hystrix patula), and false melic grass (Schizachne purpurascens). The host plants of a northern population include sedges (Carex species).
The species overwinters in the larval stage. Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Elk Island National Park | 🇨🇦 Canada | |
| 2 | Riding Mountain National Park | 🇨🇦 Canada | |
| 3 | Isle Royale National Park | 🇺🇸 United States | |
| 4 | Shenandoah National Park | 🇺🇸 United States | |
| 5 | Acadia National Park | 🇺🇸 United States | |
| 6 | Great Smoky Mountains National Park | 🇺🇸 United States |
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Washington | 🇺🇸 United States | |
| 2 | Edmonton | 🇨🇦 Canada | |
| 3 | Chicago | 🇺🇸 United States | |
| 4 | Baltimore | 🇺🇸 United States | |
| 5 | Toronto | 🇨🇦 Canada | |
| 6 | Minneapolis [Saint Paul] | 🇺🇸 United States | |
| 7 | Montreal | 🇨🇦 Canada |
Rare
Under 5% of wildlife watchers report a Northern Pearly-Eye sighting in Baltimore on a given day, based on 10 verified sightings from GBIF citizen-science data. It is the 400th most-seen of the 705 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.
August
In that month about 10% of wildlife watchers report a Northern Pearly-Eye in Baltimore on a given day, against under 5% in September to July, the lowest months.
Between 10 am and 1 pm
Across all the parks we cover, that three-hour window holds the most Northern Pearly-Eye sightings with a recorded time, and about 9 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
4th of 7
Of the 7 cities where we can rate Northern Pearly-Eye sightings, Baltimore ranks 4th at under 5%. The best odds are in Washington (United States, about 10%), Edmonton (Canada, about 10%) and Chicago (United States, under 5%).
Same family: Nymphalidae
The closest relatives of the Northern Pearly-Eye that you can see in Baltimore (family Nymphalidae, Brush-footed Butterflies) are Monarch (about 30%), Common Buckeye (about 20%) and Pearl Crescent (about 10%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Northern Pearly-Eye is recorded against all the insects logged in Baltimore (10 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.
