Cabbage White Butterfly Brad Smith/Flickr

Cabbage White Butterfly

Pieris rapae

Did You Know?

  • An introduced species from Europe, first recorded in Melbourne in 1929
  • It has become a pest, feeding on cabbages and other vegetables
  • Two species of wasp introduced to control it have helped reduce the number and impact of the butterfly
FactBox Image

The caterpillar (larva) is initially pale yellow with fine hairs, before turning green. It has narrow yellow lines on its body which are sometimes hard to see. The upper side of the butterfly (adult) is white with a black tip on its forewing (front wing) and a black patch on the front edge of its hindwing. A male has one black spot on its forewing, while a female has two black spots. Looking from underneath, the forewing is white with two black spots and the hindwing is yellow.

Size

Caterpillar about 3.5 cm; Butterfly up to 5 cm wingspan.

Behaviour

Diet

Caterpillars eat mainly the leaves of cultivated and introduced plants in the family Brassicaceae (such as cabbage and cauliflower), and can be a major pest of these crops. Adults feed on nectar from a variety of plants. Before it starts to eat, a caterpillar lays down silk to which it attaches itself for support.

Movement

When resting, a caterpillar aligns itself with the leaves of the host plant so that the yellow lines on its body look like the veins of the leaf, but if strongly handled or attacked, it ejects a fluid which can act as a repellent.

Flight

Adults start flying from early spring.

Breeding

The females lay single eggs on the underside of host leaves. The eggs hatch into caterpillars after about four days and the caterpillars then eat for 17 days, before becoming pupae for eight days. They finally emerge as white butterflies. There may be several generations each year.

Species: WhatToObserve Image

What to Observe

  • Presence (to establish the first and last sighting for the season)

  • Courting/Mating

  • Egg laying

  • Chrysalis (butterfly emerging from its shell)

Species: WhenAndWhere Image

When and Where

When To Look

From early spring around September. Butterflies fly for more of the year in warmer areas.

Where To Look

  • All over Australia, but more widespread in the south.
  • Widespread in urban areas, forests and woodlands
  • Common wherever vegetable plants are found, so generally occurs around human habitation and urban gardens
  • Look on the leaves of vegetable plants for caterpillars, and around flowers for butterflies
Species: WhatElse Image

What Else?

Similar Species

Another white butterfly won’t have the two or three black spots on the upper side of the forewing. Also, the underside of its hindwing won’t be yellow.