Riband Wave
Idaea aversata

The riband wave is a moth of the family Geometridae. The species was first described by Carl Linnaeus in his 1758 10th edition of Systema Naturae. Source
Where it is now
In the last 8 weeks this insect was recorded 75 times across 7 areas (each area is a 5 degree square).
See the Riband Wave on the live map
Movement and weather
Each season it is first heard regularly where daytime highs are around 19°C (typically 17 to 21°C, from 10 areas). That holds across 20° of latitude, which suggests its timing follows temperature more than the calendar.
Over the weeks it was present in the past year, its centre in Europe ranged from 48°N in June to 57°N in August, about 1,000 km apart.
Arrival dates
The week it was first heard regularly in each region, after at least six weeks away. Dates differ from south to north, so a region has a range.
| Region | First arrival | Last arrival | Typical peak | Areas |
|---|---|---|---|---|
| Europe | 18 May 2026 | 22 June 2026 | 29 June 2026 | 10 |
Figures are effort corrected and come from automatic sound identification, which makes mistakes. How this is measured and how it compares with human observers.