Hampshire and Isle of Wight Butterfly and Moth Society
Hampshire and Isle of Wight Butterfly and Moth Society
| Family: | Pieridae |
| Subfamily: | Pierinae |
| Genus: | Pieris |
| Species: | napi |
| Authority: | (Linnaeus, 1758) |
This is a common butterfly of damp grassland and woodland rides and is often mistaken for its cousin, the Small White. It can be found from spring through to autumn in parks and gardens, as well as less-urban areas such as meadows and woodland rides. The so-called green veins on the underside of the adults are, in fact, an illusion created by a subtle combination of yellow and black scales. This is one of the most widespread species found in the British Isles and can be found almost everywhere although it is absent from Shetland and areas of the Scottish Highlands. It is also a highly-variable species and populations have been distinguished based on an analysis of androconial scales as documented in Warren (1967), Warren (1968), Thomson (1970b) and other articles.
| #Individuals | #Tetrads | 2022 | 2023 | Abundance Trend | 2022 | 2023 | Distribution Trend |
|---|---|---|---|---|---|
| 4778 | 4342 | -9% | 477 | 527 | +10% |
| #Records | #Individuals | Earliest Record | Latest Record | |
|---|---|---|---|---|
| All Records | 63,415 | 134,254 | 03/03/1989 | 05/11/2017 |
| 2023 | 2,520 | 4,342 | 6/4/2023 | 17/10/2023 |
| Location | Date | Quantity | |
|---|---|---|---|
| Earliest Record | Hill Head | 6/4/2023 | 1 |
| Latest Record | Greywell | 17/10/2023 | 1 |
| Highest Count | Basingstoke | 17/7/2023 | 34 |
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: 359.08
Average #Recorders: 359.08