Catch a Caterpillar!thecaterpillarconundrum.org/wp-content/uploads/... · Well if you like hot chips, or apples and pears, this information is important to you! Potato crops and orchards

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Catch a Caterpillar!

Do you want to be a citizen scientist, and help researchers

learn about the world we live in? Be part of The Caterpillar

Conundrum project, and help scientists learn about caterpillars

and their parasitoids!

Contents:

Background information: Page 2

About the project: Page 3

How to participate: Page 4

Worksheet: Page 9

Student Certificate: Page 10

You can find out more about the project at

www.TheCaterpillarConudrum.org, including pages on ‘what happens in

the lab’, and curriculum links for teachers.

Like us on Facebook! www.facebook.com/TheCaterpillarConundrum

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Background information

What’s a parasitoid?

Parasitoids are animals that live on or in other animals, and feed off them to survive. They are

parasites, like the head lice you might have been infected with in primary school. A parasite normally

doesn’t kill their host (the animal they’re living on) but a parasitoid does. The parasitoids we are

studying are insects like flies and wasps that lay their eggs in caterpillars.

A parasite is a living thing that must live on or in another living thing to survive. Some parasites you

may have encountered before are animals like head lice, which live on human scalps and feed on

blood. Have you ever been bitten by a leech? They’re parasites too! Mites and gut worms are other

common parasites of humans, and there are even plants that are parasites of other plants! Parasites

tend to keep their host (the living thing they are feeding from) alive for a long time.

A parasitoid, unlike a parasite, often kills their host as part of their lifecycle. When a parasitoid wasp

lays her eggs inside the host, the eggs hatch and the baby wasps (larvae) eat the host slowly from

the inside, being careful not to kill the host too quickly. When they have grown enough, the larvae

eat their way out of the host, which normally kills it, and form cocoons on the body of the host. The

larvae undergo metamorphosis in their cocoon and emerge as adult wasps.

An endoparasitoid lives inside their host, whilst an ectoparasitoid lives on the outside of their host,

such as on the hair or skin. The particular group of wasps we are studying are endoparasitoids that

live inside caterpillars of butterflies or moths. They are important as natural enemies of caterpillars,

keeping their populations in balance, and also as biological control agents. Biological control agents

are animals (or other organisms like bacteria, viruses or plants) that are used by farmers to reduce

pest numbers. Some parasitoid wasps are used in crops to keep pest caterpillars from building up

large population numbers where they can badly damage the plants.

What’s a citizen scientist?

A citizen scientist is anyone who wants to be part of real science and help professional

researchers discover new things.

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About the project

What is the Caterpillar Conundrum project?

We are asking volunteers to rear caterpillars that they find in their backyard or local park, and we

will then upload the photos and data to a BowerBird Project. A small number of these caterpillars

will have parasitoids inside them, which will form cocoons on the body of the caterpillar and emerge

as wasps or flies. If this happens, we’ll ask the volunteer to send in their parasitoids and dead

caterpillar so we can sequence the DNA. The DNA will help us learn about the relationships between

parasitoids and their hosts.

Why do we need the help of citizen scientists?

This is real science, and we really do need your help! Rearing caterpillars takes time, and only a small

number get infected by parasitoids. To collect enough information, we need to rear hundreds of

caterpillars… a big job for one PhD student! The more information we collect, the better we can

understand how the caterpillars and parasitoids interact.

Why do we want to know about caterpillars and parasitoids?

Well if you like hot chips, or apples and pears, this information is important to you! Potato crops and

orchards are just a couple of examples of farming crops that battle with caterpillars eating their

plants on a daily basis. Whilst these caterpillars have an important place in nature, we don’t want

them taking over our crops. Parasitoids are an important part of solving this problem. By releasing

parasitoids into their crops to reduce caterpillar numbers, farmers don’t need to spray as many

pesticides, which kill beneficial insects too. The parasitoids are what we call biological control

agents… like the secret agents of the farming world.

Before we can know what parasitoids might be useful, however, we need to know how they are

related to each other and what caterpillars they infect – that’s where you come in!

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How to participate

Step 1: Find and rear a caterpillar

Step 2: Take pictures and fill out the worksheet (page: 9)

Step 3: Release your butterfly or moth

Step 4: If you find parasitoids, send them to us!

Step 5: Tell your teacher or parent you’ve completed the project, give them your photos and

worksheet and they’ll send us the information to share with the project!

Teachers and parents: Please email worksheets and associated photographs to

[email protected] so that they can be uploaded to the citizen science project, or

upload them yourselves using the instructions at

http://thecaterpillarconundrum.org/participate/how-to-upload-your-data/

Step 1: Find and rear a caterpillar

Step 1: Make a home for your caterpillar!

Find a large jar or other container. Clear containers work best, so you

can see what’s happening inside. Wash your container, rinsing out any

detergent residue. Put some dirt or sand at the bottom of your container

– this will help keep the humidity stable for your caterpillar. Find some

really fine flyscreen (if you do happen to have parasitoids emerge, they

are really tiny and we don’t want them to escape!) or poke some holes

in a piece of baking paper with a pin. Use an elastic band or hair tie to

hold the flyscreen or baking paper over the top of the container.

This is our caterpillar home. It still needs some more leaves so the

caterpillar has lots to eat.

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Step 2: Find your caterpillar!

Caterpillars come in all colours and sizes. Look for plants in your backyard or local park that look like

they’ve been nibbled on… it’s a good indicator that there are caterpillars around! Some caterpillars

are more active at night, when there is less chance of them being eaten by birds. Collecting in

National Parks or Conservation Reserves is not permitted without a permit.

For this project we are particularly interested in caterpillars that live on native Australian plants, but

you are welcome to try rearing any species of caterpillar that you can find. If you find a caterpillar

not on a plant (for example walking along your porch) it’s not a good idea to collect them unless you

are sure you know what plant they like to eat. Caterpillars are very fussy eaters!

Moth caterpillar image by Ken

Walker, BowerBird. Image

licence: Creative Commons

Attribution Non-Commercial

Share-Alike.

Step 3: Catch your caterpillar!

Don’t touch caterpillars with your bare skin. Caterpillars can irritate our skin, or we can easily hurt

them (or the parasitoids inside them). Use a leaf or twig to transport your caterpillar to their new

home. Put some of the plant you found it on inside the jar too – caterpillars are very hungry!

Step 4:

1) Take a picture of your caterpillar and save it somewhere safe.

2) Fill out the first section of the worksheet

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Step 5: Look after your new friend

You will need to replace the plant every few days as it dries out or gets eaten, so make sure you can

access more. Caterpillars can be very picky eaters, so it’s important you remember which plant you

found it on. You may also need to clean out the bottom of the jar because caterpillars eat a lot…

which means caterpillars poo a lot!

Step 6: Caterpillar Cocoon

If your caterpillar forms a cocoon, you need to be patient and check it every day to see if a butterfly

or moth has emerged. Make sure there are some twigs or stems in the container for the new

butterfly to hold on to when drying its new wings.

Caterpillars can form

cocoons of many different

types. This is a moth in

the family Anthelidae.

Image by Suzanne Jones,

BowerBird. Image licence:

Creative Commons

Attribution Non-

Commercial Share-Alike.

Step 7:

1) Take a picture of your cocoon

2) Fill out the second part of the worksheet

Step 8: Wait patiently for your adult butterfly or moth to emerge

Caterpillars can remain inside their cocoons for a long time. It may be days, weeks, or even months

before it emerges as an adult butterfly or moth. Be patient, don’t forget about it, and don’t lose

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hope! You can occasionally spray your cocoon with a mist of water to stop it drying out – but not too

often, or it might grow mould.

Whilst you are waiting for your butterfly or moth to emerge from the cocoon, why not take part in

some different citizen science projects?

Step 9: When your adult butterfly emerges:

1) Take a picture of your butterfly or moth

2) Fill out the third part of the worksheet

Butterflies will die quickly if left in a jar for too long, so once your adult emerges and you have taken

some photos, release your transformed butterfly or moth into the same location you collected the

caterpillar.

Snap a picture of your butterfly or moth before releasing

it! Image by Ken Walker, BowerBird. Licence: Creative

Commons Attribution Non-Commercial Share-Alike

Did you get a parasitoid instead of a butterfly?

Was your caterpillar infected with parasitoids? You may see the parasitoid larvae emerging, or you

might just see the cocoons they make on the body of the dead caterpillar. If you do have some

parasitoids, please collect them for us! Ask your parents or coordinator to give us a call on (08) 8313

8246 and we’ll give you some more information and send you out some containers and a reply paid

envelope to send them back to us!

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Parasitoid wasp cocoons (on the remains of a

caterpillar!) Photo by Martin Lagerwey on

BowerBird. Licence: Creative Commons

Attribution Non-Commercial Share-Alike.

My caterpillar died but there’s no parasitoids?

Some species of caterpillar can be difficult to rear. They might die of a fungal infection, or simply not

be able to cope with the change in environmental conditions. Don’t be disheartened. Try rearing a

different species of caterpillar, making sure you wash the container out well before making a new

home.

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Name:

Don’t forget to take a photograph of your caterpillar!

Don’t forget to take a photograph of the cocoon!

Don’t forget to take a photograph of the butterfly or moth!

Part one: fill out when you find a caterpillar What date did you find your caterpillar?

What is the postcode where you found your caterpillar?

Can you describe where you found your caterpillar? What sort of plant was it on? (For example, did you find it on a mint plant, or a gum tree?)

Can you describe your caterpillar? You might want to talk about the colour and shape. Does it have spines or patterns? How big is it? (You might want to use a ruler to measure it).

Part two: fill out when your caterpillar makes a cocoon What date did your caterpillar make a cocoon?

Can you describe the cocoon? What does it look like?

Part three: fill out when your butterfly or moth comes out the cocoon What date did the butterfly or moth come out?

Can you describe it? What does it look like?

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