Stygionympha vigilans
In 3 days ~20% in a week ~40%
Stygionympha vigilans, the western hillside brown, is a butterfly of the family Nymphalidae. It is found in South Africa on the seaward side of the mountains from Cederberg south to the Cape Peninsula in the Western Cape and along the Drakensberg mountains to Grahamstown in the Eastern Cape.
The wingspan is 45–48 mm. Adults are on wing from October to December and from August to April (with peaks from October to November and February). There are probably multiple generations per year. The larvae feed on Poaceae grasses. Larvae have also been reared on Ehrharta erecta and Ischyrolepsis cinncinnata. Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Table Mountain National Park | 🇿🇦 South Africa |
More parks will be added in future updates.
With luck
About 10% of wildlife watchers report a Western Hillside Brown sighting in Table Mountain National Park on a given day, based on 84 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 61st most-seen of the 344 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.
September to April
In those months about 10% of wildlife watchers report a Western Hillside Brown in Table Mountain National Park on a given day, against under 5% in May to August, the lowest months.
Between 10 am and 1 pm
Across all the parks we cover, that three-hour window holds the most Western Hillside Brown sightings with a recorded time, and nearly all of them come between 6 am and 6 pm: it is a daytime animal.
Only Table Mountain National Park, in our data
Table Mountain National Park is the only park on Wallace's Line with enough records to rate Western Hillside Brown sightings: about 10% of wildlife watchers there report one on a given day.
Same family: Nymphalidae
The closest relatives of the Western Hillside Brown that you can see in Table Mountain National Park (family Nymphalidae, Brush-footed Butterflies) are Garden Acraea (about 30%), Cape Autumn Widow (about 20%) and Painted Lady (about 20%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Western Hillside Brown is recorded against all the insects logged in Table Mountain National Park (84 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.
