Description: Wingspan 38-57mm. Adults have white forewings with black tips and uniform yellow underside to the hindwings. Females on average are larger than males and have more extensive dark markings. Second brood specimens of both sexes are darker than those of spring broods. April to October in two overlapping broods. The second brood is much larger than the first, with local numbers augmented or swamped by immigrants.

World Distribution: Throughout Europe, NW Africa, Asia to Japan. Introduced into N. America and Australia.

Irish Distribution: This is a resident species whose numbers are annually augmented by migrants. It is recorded from all parts of N. Ireland, absent only from upland parts.

Ecology: Adults live in loose open populations. They roam the countryside looking for nectar and foodplants. They are attracted to many types of flowers, but especially pale and white flowers. Larvae feed on cultivated and wild cabbages Brassica spp, and Nasturtium Tropaeolum majus especially those growing in sheltered sites such as gardens and field margins. The green larvae are solitary resting along the midrib of the foodplant and relying on camouflage. The pupa overwinters.

Key Identification Features:

• Upperwing pattern especially extent of black marking along costal and side margins of forewing
• Uniform yellow colour on the underside of the hindwing

Distribution Map from NBN: Pieris rapae at National Biodiversity Network mapping facility, data for UK.

iNaturalist: Pieris rapae at iNaturalist World Species Observations database.