Hampshire and Isle of Wight Butterfly and Moth Society
Hampshire and Isle of Wight Butterfly and Moth Society
| Family: | Hesperiidae |
| Subfamily: | Hesperiinae |
| Genus: | Hesperia |
| Species: | comma |
| Authority: | (Linnaeus, 1758) |
This warmth-loving skipper is relatively-local, but is fairly easy to identify, since it is the only skipper found in the British Isles that has the distinctive white spots on the underside of the hindwings, which give the butterfly its name. Like other "golden" skippers, the male is distinguished from the female by the sex brand on its forewings, which is a line of specialised scent scales. This butterfly is restricted to closely-grazed chalk downland sites in southern England. Its former range extended from South Somerset in the west to isolated colonies in the north as far as Westmorland and North-east Yorkshire. Its range contracted in the 20th century due to a reduction in grazing stock as well as the onset of myxomatosis which severely affected rabbit populations. Recent years have been more promising and this is one of the few species that is increasing its range. This species is not found in the Channel Islands.
| #Individuals | #Tetrads | 2022 | 2023 | Abundance Trend | 2022 | 2023 | Distribution Trend |
|---|---|---|---|---|---|
| 484 | 268 | -44% | 14 | 15 | +7% |
| #Records | #Individuals | Earliest Record | Latest Record | |
|---|---|---|---|---|
| All Records | 2,899 | 18,619 | 11/07/2018 | 11/10/1986 |
| 2023 | 69 | 268 | 25/7/2023 | 14/9/2023 |
| Location | Date | Quantity | |
|---|---|---|---|
| Earliest Record | Oxenbourne Down | 25/7/2023 | 1 |
| Latest Record | Old Winchester Hill transect: Section 3 | 14/9/2023 | 1 |
| Highest Count | Old Winchester Hill | 8/9/2023 | 40 |
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: 24.68
Average #Recorders: 24.68