Large white  (Pieris brassicae)

This widespread and common species is not threatened; it is not listed under any conservation designations.

This familiar, strong-flying species is our largest white butterfly (2), and is often an unwelcome visitor to gardens because the caterpillars damage cabbages and other realated crops (2). Females are distinguished by two black spots and a black streak on the fore-wings (1). In both males and females, the undersides of the wings are yellowish with black flecking (1). The caterpillar grows up to 4 cm in length, and is generally pale green with black spots, with a yellow line along the back and one along each side (3).

Widespread and common throughout Britain, and occurs on most offshore islands (2).

You can view distribution information for this species at the National Biodiversity Network Gateway.

The caterpillars feed on wild or cultivated crucifers (members of the cabbage family), and prefer cultivated cabbages and Brussels-sprout (varieties of Brassica oleracea), as well as oil-seed rape (Brassica napi) (2). It is therefore usually seen close to farms and gardens (2).

Typically, two generations are produced each year (3). The first brood of adults emerges in spring and flies until April. A second, larger brood of adults appears in July (2), and in particularly warm years, a third brood may occasionally occur (2). The eggs are laid in batches, on leaves of the foodplants (2), hatching after around a week (3). In their early stages, the caterpillars live in groups (2), and can be extremely damaging, reducing the foodplant to a mere skeleton (3). They become solitary later on in life (2), and are very distasteful to birds because they consume mustard oils from their diet (2); their bright colouring advertises this fact, protecting the caterpillars from attack (3). Members of the broods produced later in the year hibernate through the winter as a white pupa(2) attached to walls, fences, tree trunks and occasionally the foodplant (3).

This butterfly is not currently threatened.

Conservation action has not been targeted at this common and widespread species.

View information on this species at the UNEP World Conservation Monitoring Centre.

There may be further information about this species available via the National Biodiversity Network Gateway.

For more on this species see: Asher, J., et al. (2001) The Millennium Atlas of Butterflies in Britain and Europe. Oxford University Press.

For more on butterflies and their conservation see the Butterfly Conservation website:
http://www.butterfly-conservation.org