Hampshire and Isle of Wight Butterfly and Moth Society
Hampshire and Isle of Wight Butterfly and Moth Society
| Family: | Hesperiidae |
| Subfamily: | Pyrginae |
| Genus: | Pyrgus |
| Species: | malvae |
| Authority: | (Linnaeus, 1758) |
Like most skippers, the Grizzled Skipper is extremely difficult to follow when in flight, but will stop to feed from various nectar sources. Once settled, the black and white pattern on the wings, from which this species gets its name, is unmistakable. The butterfly occurs in small colonies of less than 100 adults. A well-known aberration of this species, ab. taras, has all of the white spots on the forewings joined, forming a large white blotch. This butterfly is found in England south of a line extended from West Gloucestershire in the west to North Lincolnshire in the east, with strongholds in central and southern England. There are scattered colonies further north and in Wales. This species is absent from Scotland, Ireland, the Isle of Man and the Channel Islands.
| #Individuals | #Tetrads | 2022 | 2023 | Abundance Trend | 2022 | 2023 | Distribution Trend |
|---|---|---|---|---|---|
| 853 | 930 | +9% | 57 | 58 | +1% |
| #Records | #Individuals | Earliest Record | Latest Record | |
|---|---|---|---|---|
| All Records | 9,448 | 24,395 | 02/04/2009 | 07/09/2004 |
| 2023 | 309 | 930 | 20/4/2023 | 22/6/2023 |
| Location | Date | Quantity | |
|---|---|---|---|
| Earliest Record | Magdalen Hill Down Original transect: Section 10 | 20/4/2023 | 1 |
| Latest Record | Mottistone Down transect: Section 3 | 22/6/2023 | 1 |
| Highest Count | Compton Down | 27/5/2023 | 51 |
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: 68.2
Average #Recorders: 68.2