Idaea inversata
In 3 days ~20% in a week ~40%
Idaea inversata, the purple wave, is a moth of the family Geometridae. The species was first described by Achille Guenée in 1857. It is found along the east coast of Australia. Idaea inversata is externally very similar to I. costaria but lacks the two-coloured head pattern of that species. I. costaria has a creamy-white patch between the antennae, whereas I. inversata is dark reddish throughout this area. Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Lamington National Park | 🇦🇺 Australia | |
| 2 | Blue Mountains National Park | 🇦🇺 Australia | |
| 3 | Great Otway National Park | 🇦🇺 Australia |
With luck
About 10% of wildlife watchers report a Purple Wave sighting in Great Otway National Park on a given day, based on 9 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 226th most-seen of the 418 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.
January, March–April and October–November
In those months about 10% of wildlife watchers report a Purple Wave in Great Otway National Park on a given day, against under 5% in February, May–September and December, the lowest months.
Between 7 and 10 pm
Across all the parks we cover, that three-hour window holds the most Purple Wave sightings with a recorded time, and about 6 in 10 of them come between 6 pm and 6 am: it is most active around dawn and dusk.
Among the best
Of the 3 parks where we can rate Purple Wave sightings, Great Otway National Park ranks 3rd at about 10%, level with the leaders once rounded. The best odds are in Lamington National Park (Australia, about 10%) and Blue Mountains National Park (Australia, about 10%).
GBIF citizen-science records
It is estimated from how often the Purple Wave is recorded against all the insects logged in Great Otway National Park (9 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.
