|
back to organism index
PAINTED LADY BUTTERFLIES
Painted lady butterflies can be purchased from a biological supply
house as small fuzzy larvaemaybe as small as 1 cm (1/2")
long. They arrive in a plastic container with a centimeter or
two of green goop that looks like guacamole. The ventilated lid
holds a piece of filter paper over the top of the container. Keep
the lid and paper on the container at all times. The painted ladies
will spend all of their larval days, perhaps 2 weeks or a little
more, in the container eating the food layer, molting, and growing
to a length of 4 cm (1-1/2") or a little more. They require
no special attention other than to keep them in a well-lighted
area, but out of direct sun and safe from temperature extremes.
After the larvae are about 2 cm (3/4") long, it is all right
for students to remove the larvae from the containers from time
to time for close observation of structures and behaviors.
Life cycle. In due course the larva receives
a biological message to climb to the top of the container, spin
a little knob of silk onto the filter paper, and attach its rear
end firmly to the knob. The larva hangs head down and assumes
a characteristic J shape, indicating that pupation is only a few
hours away. If you are vigilant, you might be able to observe
the final molt as the fuzzy outer skin splits near the head to
reveal the smooth, curiously molded, slightly iridescent pupa
ensconced in its chrysalis. As the pupa writhes around, the skin
is pushed up and off the body until it is a crunchy little nub
pressed up against the paper. The painted lady lapses into a period
of relative quietude, hanging motionless except for brief fits
of wriggling, especially when disturbed. At this time the pupae
attached to the paper should be moved to a larger cage.
For a week or 10 days the pupa undergoes dramatic physical and
biochemical transformations. The chrysalis gradually darkens until
it is dark gray-brown, and the orange color of the wings starts
to show through. This is when you can expect the adult to emerge,
which happens quickly. The chrysalis shell splits near the bottom
(head end), and the butterfly reaches out with its legs and grasps
the outside of the chrysalis. The head comes out, and then the
abdomen and wings are pulled free of the chrysalis shell. The
emergence takes a minute or less.
The fresh new butterfly clings to the chrysalis shell with its
soft, crumpled wings hanging down. Over the next hour or two the
abdomen pulses as it pumps fluid into the veins of the wings,
expanding them to their fully extended shape. During this time
the butterfly ejects a splat of red liquid. Students may be alarmed,
thinking it is blood, but it is a waste fluid that the butterfly
unloads as it prepares for its new life. In 3 or 4 hours the butterfly
takes wing as a flying insect.
Maintenance. Painted lady butterflies don't
require much as adults. They will drink dilute sugar solution
and fly around looking for mates. Place the cage where sunshine
will fall on it for a few hours each day. If mallow, a common
weed in many parts of the country, is available, you can place
a small bouquet of leaves in a vial of water. After the butterflies
mate, they will lay eggs on the mallow leaves. If you want to
raise a second generation of painted lady butterflies, provide
mallow leaves for the larvae to eat.
After a month the adults will die, not because of any ill effects
caused by captivity, but because that is their normal life span.
Even though it is never advisable to release study organisms into
the environment, if a painted lady butterfly "escapes,"
it will not be an environmental disasterpainted ladies are
already well established throughout the country.
Order butterfly larvae. Painted lady butterfly
larvae are available from several biological supply companies.
They arrive in a container of food and will advance through their
entire larval stage without ever leaving the container. They are
usually sold three to five in a container. It is nice to have
about ten larvae (two containers), but the activity will be a
great success with one container. The larvae can usually be delivered
about 24 weeks after you call in your order.
Use local larvae. If you have local painted
lady larvae, or another species of butterfly larvae available,
use them instead of commercially available larvae. You will need
to research appropriate food sources for each type of butterfly
larvae.
What to do when they arrive. Butterfly larvae
are shipped with their own food in the shipping container. Warmer
temperatures will encourage larvae to grow more quickly. Maintain
container out of direct sunlight. No further care is necessary,
as they will pupate within 7 to 10 days. (See above)
Prepare a feeding station. A butterfly feeding
station can be made from a standard insect water fountain. Use
a hole punch to make a hole in the center of the cap of a vial.
Roll up an 8-cm (3") square of paper towel and push it through
the hole in the cap. Push the vial into the plastic vial holder
to prevent the fountain from tipping over.
Butterflies feed by sipping nectar through their long coiled
proboscis. A substitute nectar can be made with sugar and water.
Put 1/4 teaspoon of sugar in a vial and fill it with water. Attach
the wick cap to the vial. Cut a crude flower from a piece of red
or orange paper, make several criss-cross cuts in the center,
and push the vial through. The flower will attract the butterflies
and give them a place to land.
Provide mallow leaves (optional). When adults
emerge, provide a bouquet of fresh mallow leaves in the cage.
Use the hole punch to punch a few holes in a plastic cup lid.
Fill the cup with water and snap on the lid. Stick leaves and
small branches of mallow through the holes. Females will lay eggs
on the mallow leaves.
Watch for egg hatching. The eggs hatch in a
week or so, and it is possible to start the whole process over
again. Larvae will thrive if you transfer them to fresh mallow
leaves. They must be kept in a covered container because they
are very mobile. A supply of mallow leaves can be kept in the
refrigerator. If you do not want to let the eggs hatch, put them
in the freezer for a few days.
Discuss death. Butterflies don't live long.
After 3 weeks they will be tattered and tired. With luck they
will have fulfilled their destiny by producing eggs. Discuss the
inevitability of the death of the butterflies and that it is not
caused by captivity or the result of any failing on the part of
the caregivers. Butterflies just don't live very long.
Back to top
|