Where to see
Habitat: Woods, hedgerows and scrubby grassland. Often visits gardens, especially in late summer to seek nectar so they can fatten up to survive the winter. In winter it tends to hide in evergreens such as ivy and holly.
Caterpillar foodplants: Buckthorn; on limestone/chalk it is Purging Buckthorn; on more acid soils it is Alder Buckthorn.
Best places: Widespread.
When to see
Single brooded. Most likely to be seen from Feb/March through to Oct/Nov, though numbers may be low in June/July while it is breeding. It overwinters as an adult.
Sightings by month (last 5 years)*:
Sightings this year*:
A large butterfly, the male being bright lemon yellow and the female whitish in flight but can look pale green at rest. It always lands with its wings closed: you very rarely see the upperside.
The male is sometimes mistaken for a Clouded Yellow, but that butterfly is a deeper golden, almost orange colour. The female can be mixed up with the Large White at a distance, but if it lands, you can see the wings are a very different shape, with pointed tips.
The Brimstone has a very long proboscis, so it can nectar on flowers which most other UK butterflies cannot, such as runner beans and teasels. It has a preference for purple/pink flowers.
This is an early-to-bed butterfly, settling down for the night around 3.00-4.00pm.
Despite the bright colour of the male, it can be remarkably difficult to see when it lands among leaves – the veins which are quite prominent on the underwings resemble the veins of leaves.
*Note: The charts shown on this page are drawn only from casual sightings submitted to this website. Records from this website will be added to a lot more data collected throughout the year and used to compile the five-yearly Butterfly Atlases for Dorset and the UK.