Heteronympha merope
In 3 days ~70% in a week ~90%
Heteronympha merope, the common brown, is a species of butterfly of the family Nymphalidae, endemic to the southern half of Australia. The wingspan is about 60 millimetres (2.4 in) for males and 70 mm (2.8 in) for females.
The larvae feed on Poaceae species, including Brachypodium distachyon, Cynodon dactylon, Ehrharta erecta, Poa poiformis, Microlaena stipoides, Poa tenera and Themeda triandra. The common brown butterfly is emerging ten days earlier than it did 65 years ago due to the effects of climate change.
Schlossmann, Jessie. "Climate Change Causing Butterflies to Emerge Ten days Early". Australian Geographic 3-23-10 [1] South Australian Butterflies Data Sheet.[2] Media related to Heteronympha merope at Wikimedia Commons Data related to Heteronympha merope at Wikispecies Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Maria Island National Park | 🇦🇺 Australia | |
| 2 | Wilsons Promontory National Park | 🇦🇺 Australia | |
| 3 | Grampians National Park | 🇦🇺 Australia | |
| 4 | Great Otway National Park | 🇦🇺 Australia | |
| 5 | Freycinet National Park | 🇦🇺 Australia | |
| 6 | Blue Mountains National Park | 🇦🇺 Australia | |
| 7 | Kosciuszko National Park | 🇦🇺 Australia | |
| 8 | Royal National Park | 🇦🇺 Australia | |
| 9 | Booderee National Park | 🇦🇺 Australia | |
| 10 | Lamington National Park | 🇦🇺 Australia | |
| 11 | Springbrook National Park | 🇦🇺 Australia |
Possible
About 30% of wildlife watchers report a Common Brown sighting in Blue Mountains National Park on a given day, based on 234 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 3rd most-seen of the 789 insects we can rate there. Over three days the chance rises to about 70%, and over a week to about 90%, if each day is a fresh chance.
March and November–December
In those months about 40% of wildlife watchers report a Common Brown in Blue Mountains National Park on a given day, against under 5% in June to September, the lowest months.
Between noon and 3 pm
Across all the parks we cover, that three-hour window holds the most Common Brown sightings with a recorded time, and about 9 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
6th of 11
Of the 11 parks where we can rate Common Brown sightings, Blue Mountains National Park ranks 6th at about 30%. The best odds are in Maria Island National Park (Australia, about 40%), Wilsons Promontory National Park (Australia, about 40%) and Grampians National Park (Australia, about 40%). All parks ranked.
Same genus: Heteronympha
The closest relatives of the Common Brown that you can see in Blue Mountains National Park (genus Heteronympha) are Banks' Brown (about 10%) and Spotted Brown (about 10%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Common Brown is recorded against all the insects logged in Blue Mountains National Park (234 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.
