Orchard Swallowtail Butterfly
- Colour: the caterpillar (larva) is initially green, white and brown and resembles bird droppings!
- A mature caterpillar has a dark brown head, a green body with some pale yellow and brown markings, and spines along its back.
- The male butterfly (adult) is black with an arc of creamy-white spots near the tip of each forewing (front wing). Each hindwing (back wing) has a creamy-white patch and a single red spot, and there are many red crescents on its underside.
- The female butterfly is brown to black, and the outer half of its forewing is whitish-grey. Its hindwing has a creamy-white patch, as well as a series of blue and red crescent-shaped markings.
- Size: caterpillars are up to 6 cm long; butterflies have a 10 – 12 cm wingspan.
- Diet: the caterpillar eats the leaves of many plants, particularly citrus and native species from the Family Rutaceae; it prefers to eat young leaves but large caterpillars will eat older leaves. The butterfly feeds on nectar from a variety of plants, particularly lantana.
- Movement: if disturbed, a caterpillar will reveal a red-orange “tentacle” (known as the osmeterium) from behind its head which emits a foul smell to deter predators.
- Flight: generally slow and erratic unless disturbed, and females fly more slowly during the egg-laying period. The males tend to “patrol” flight paths.
- Breeding: females lay eggs on the underside of host leaves, and the eggs hatch one week later.
What to Observe
- Presence (to establish the first and last sighting for the season)
- Egg laying
- Chrysalis (butterfly emerging from its shell)
ClimateWatch Science Advisor
We expect butterflies to appear earlier in the year as a result of climate change warming the Earth. They may also start appearing in new areas as warmer temperatures enable them to live in environments that were previously too cold for them.
When To Look
- From October through to May
- The caterpillar eats for four weeks, then becomes a pupa for two weeks before emerging as a butterfly.
Where To Look
- Along eastern Australia, from Cape York in northern Queensland to South Australia, but is rare in southern Victoria and South Australia as it prefers more humid tropical and subtropical conditions.
- In forests, woodlands and urban areas, including your backyard gardens and orchards, particularly where citrus plants are grown
- During periods of unusually high humidity it moves south during summer and autumn.
- Look on the leaves of citrus plants for caterpillars, and around flowers, particularly lantana, for butterflies.
The map below displays the accumulated observations of these species as reported by ClimateWatch observers, together with the layer showing how the range of the species might change between now and 2085, with orange areas indicating where the species might disappear, and green areas where the species range might expand.
Braby, MF 2000. Butterflies of Australia: Their Identification, Biology and Distribution. CSIRO Publishing.
Jordan, F & Schwencke, H 2005. Create More Butterflies: a guide to 48 butterflies and their host-plants for south-east Queensland and northern New South Wales. Earthling Enterprises, Brisbane.
Dingy or Dainty Swallowtail Butterfly: caterpillar is smaller (about 3.5 cm long) and dark green to black with yellow and white spots. The butterfly is also smaller (6 cm wingspan) with creamy-grey patches over its entire black forewing, and creamy-white, red and blue patches on its hindwing.
Did You Know?
Males can be territorial and will chase anything black and white that enters their territory, including Magpies!
They are considered a minor pest in citrus orchards, although are unlikely to survive long in commercial orchards due to persistent spraying.