Hampshire and Isle of Wight Butterfly and Moth Society
Hampshire and Isle of Wight Butterfly and Moth Society
| Family: | Lycaenidae |
| Subfamily: | Polyommatinae |
| Genus: | Polyommatus |
| Species: | icarus |
| Authority: | (Rottemburg, 1775) |
Living up to its name, this butterfly is the commonest blue found in the British Isles. While the male has bright blue uppersides, the female is primarily brown, with a highly variable amount of blue. This is the most widespread Lycaenid found in the British Isles and can be found almost anywhere, including Orkney. It is absent, however, from Shetland and the mountainous areas of Wales and Scotland. This butterfly forms reasonably discrete colonies measured in tens or hundreds, with individuals occasionally wandering some distance.
| #Individuals | #Tetrads | 2023 | 2024 | Abundance Trend | 2023 | 2024 | Distribution Trend |
|---|---|---|---|---|---|
| 13902 | 8235 | -40% | 696 | 455 | -34% |
| #Records | #Individuals | Earliest Record | Latest Record | |
|---|---|---|---|---|
| All Records | 85,919 | 352,850 | 04/04/2019 | 12/11/1990 |
| 2024 | 3,097 | 8,235 | 27/4/2024 | 18/10/2024 |
| Location | Date | Quantity | |
|---|---|---|---|
| Earliest Record | Hook with Warsah | 27/4/2024 | 1 |
| Latest Record | Seafield Park | 18/10/2024 | 1 |
| Highest Count | Stockbridge Down | 27/8/2024 | 104 |
One of the issues with 'raw' trend data is that there is inherent bias based on the number of recorders. For example, the number of individuals and populated tetrads recorded are likely to increase if there is an increase in the number of recorders. In order to remove this bias, the normalised trends use data that has been recalculated using the average number of recorders over the trend period. This normalisation gives a much better picture of the true trends.
Average #Recorders: 480.44
Average #Recorders: 480.44