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Wanderer Butterfly - Danaus plexippus plexippus
FAMILY NYMPHALIDAE
This page contains pictures and information about Wanderer Butterflies in the Brisbane area, Queensland, Australia.
- Male, wingspan 100mm
Wanderer is known as Monarch Butterfly in North America. The Wanderer butterfly is a large black and orange butterfly. Some consider it as the most beautiful insect in the world. Notice the above picture that there is the ‘sex mark’ on the hind-wing of this male Wanderer. The female looks the same except there is no sex mark and the black veins are slightly broader.
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- Female, laying egg.
The female Wanderers lay their eggs on underneath of the Milkweed plants leaf. They will hatch a few days later.
- Young caterpillar on Milkweed flowers, body length 10mm.
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- Grow up to 50mm
The caterpillar has yellow, white and black colour rings around its body. This colour pattern is a warning sign to the predators, such as birds, that “I am yukky and poisonous, don’t eat me.” The caterpillar has two pairs of black feelers at the head and tails end. This caterpillar is feeding on the Milkweed plant. This plant is poisonous but the caterpillar can tolerate this poison and store in their body, so both the caterpillar and adult butterfly are poisonous. Birds and other predators will avoid them.
The Wanderer Butterflies are just flying around and looking for mates freely, without any worry about predators.
Rearing Wanderer Caterpillars
On early April 2000, we collected seven caterpillars with some Milkweed back home and watched them changed to pupas and then to butterflies. It was fun. We found that the caterpillar will take about ten days to turn into a pupa. When the caterpillar is about to change into a pupa, it is 40mm in length and will climb to the top of our feeding case. Then it puts some silk to stick to the case ceiling and then it forms a ‘J’ shape. After a few hours, it starts to shake and removes it’s black-yellow and white skin and turns into a green pupa.
The first picture is a last instars caterpillar. The second picture shows, from left to right, a black dead pupa (caused by fly parasite), a green pupa which will turn into a butterfly some days later, and an empty pupa that the butterfly has already emerged from.
The above two photos show the same pupa in early stage and in final stage. The pupa is initially pale green in colour, and it is in the typical shape of a NYMPHALIDAE pupa. After about ten days, we can see the butterfly wings pattern under the transparence pupa skin. The adult butterfly emerged in the next day.
The Wanderer just come out from the pupa. If the pupa did not turn into black colour, the pupa will hang silently for about ten days, then a butterfly will come out. Most of the butterflies we raised come out at about one o’clock in the afternoon. The day before the butterfly came out, we could see the wing pattern, the head and the eyes clearly inside the pupa.
We kept the butterfly for a day or two, and then let it go to look for their future. The butterflies will look for their mates, lay eggs and start the next cycle.
Their Predators
Although the adults and caterpillars are poisonous to birds, Wanderer are not free of predators. We found that not all of the pupas will become butterflies. We had collected four large caterpillars (over 20mm) and three small one. Only one of the four large caterpillar turned into a butterfly. For the other three, after they had turned into pupas, they became black in colour. Two or three days later, we saw a white larvae, about 5mm in length, came out from the dead pupas. Those three pupas never turned into a butterfly. From the books, the dead pupas could be parasited by wasps or flies.
For the three smaller caterpillars we collected, all turned to butterflies. I guess this is because we collected them before they were found by the wasps or flies.
Besides being parasited, the Wanderer caterpillar are subjected to predation by other insects, such as the predatory Glossy Shield Bug shown in the above picture.
The Wanderer belongs to the NYMPHALIDAE butterfly family. Like all other NYMPHALIDAE, the Wanderer uses only four legs. The first pair of legs are almost invisible. See our Discussions on why NYMPHALIDAE uses only four leg.
Wanderer Butterflies Food Plants
There are a lot of Wanderers flying around the Brisbane bushlands. Wherever there is Milkweed plants, their caterpillar’s host plant, there will be a lot of Wanderer flying around. The Wanderer caterpillar will not eat other plants. Why they rely on a few types of host plants please see our Discussions
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- The "milk" from the Milkweed plant.
There are two closely related species of milkweed plants found in Brisbane. One species has the white flowers and the other has red and orange flowers. The name milkweed reference to their milky sap which is toxic and taste terrible to birds and mammals. The Wanderer Butterfly caterpillars can cope with the toxins and stores them in their body. The bird or mammal which eat the caterpillar or butterfly become poisoned. This may not kill the bird or mammal but this bad experience is strong enough to make them avoid the Wanderer for their whole life.
- Swan Plant
- Flowers, Asclepias fruiticosa or Asclepias physocarpa
- Seeds and Seed-pods, Asclepias fruiticosa or Asclepias physocarpa
The Milkweed plants are about one meter high and with white or red and yellow flowers. The plants will produce milk-white liquid if scratched. The Milkweed plants are sometimes called Swan Plant because the seed pod floats on water like a swan if it is cut off. The plant are also known as Balloon Cotton, Silkpods or Cotton Bush.
- Red-headed Cotton Bush
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- Asclepias Curassavica
The first picture show a female Wanderer laying eggs on the plant. The second picture show a male Wanderer feeding on the flower, where he may waiting for a female appear as well.
Butterfly's life cycle - Complete Metamorphosis
Summary of Wanderer Butterfly's life cycle.
The diagram shows the summary of Wanderer Butterfly's life cycle, that is typical for insects with complete metamorphosis.
- Like all other arthropods, insects cannot grow continuously because the
restriction of their hard exoskeleton. Instead they grow via a series of
moults, they will increase in size and change of appearance. Basically there
are three different ways in which insects develop into adult stage.
- Ametabolous, the egg hatch into small insect, then the small insect, after moulting, turns into a larger insect. The insect look no different in every stages. Some wingless insect, such as silverfish is develop in this way. They are known as 'complete' and 'in-complete' life cycle.
Gradual metamorphosis, also know in-complete metamorphosis. Cockroaches, grasshoppers and bugs develop with in-complete life cycle. Their young, usually called nymphs, look similar to the adults but with no wings. They share the same habitat, the same food and same lifestyle. Their wings develop externally. So we can see their wing buds and it increase in size after every moults. Details of in- complete metamorphosis of this bug are shown below.
Abrupt metamorphosis, also know as complete metamorphosis. Beetles, flies. butterflies, moths and wasps develop with complete life cycle. Their young look very different from the adults. When they just come out form eggs, they may called maggot, caterpillars, grubs or commonly called larva. Their life style is very different from their adults. Just before they become an adult, they will enter a stationary state. Then their body is completely transformed into a different shape. Their wings develop internally. Their different stages target at different function. The larva stage is mainly focus on eating and growing. The pupa stage is for transformation and the adult aims at reproduction. For details of insects complete life cycle please find at my other pages about Tachnid fly, Wanderer Butterflies and Evening Brown Butterflies.
- Reference and Link:
- 1. Insects
of Australia, CSIRO, Division of Entomology, Melbourne University
Press, 2nd Edition 1991, p897.
- 2. Insects of Australia and New Zealand - R. J. Tillyard, Angus & Robertson, Ltd, Sydney, 1926, p461.
- 3. Rear Monarchs - Monarch Watch - WWW.MonarchWatch.org
- 2. Insects of Australia and New Zealand - R. J. Tillyard, Angus & Robertson, Ltd, Sydney, 1926, p461.
