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What would you do if you found one of these bright red creatures in your yard?

pipevine caterpillarpipevine caterpillar

You should cheer because they are the caterpillars of the beautiful pipevine swallowtail butterfly (Battus philenor). We found these at the Boyce Thompson Arboretum in Arizona.

The bright red caterpillars will turn into one of these butterflies.

pipevine butterfly

Check out the gorgeous metallic blue on the lower parts.

I should admit right away that it is extremely difficult to get a good photograph of a pipevine swallowtail butterfly. The butterflies have a behavior known as “flutter feeding” which mean their wings are in almost constant motion. This one was on the floor in a public place, so I suspect it may have been stepped on. Too bad.

The caterpillars of the pipevine swallowtail feed on plants called pipevines (Aristolochia species), hence the name. The plant is a small, drab vine and is hard to spot. I am grateful to my friend who pointed out this one. Edit: My friend says this plant is Aristolochia watsonii.

pipevine plant

The plants contain a nasty chemical called aristolochoic acid that deters most animals from feeding on them. The ability to feed on pipevine plants is a unique feature of these caterpillars.

The caterpillars change size and color as they grow. You may also see pipevine caterpillars that look like the ones above, but are black instead of red.  The larger, older caterpillars are often found resting on plants besides their hosts (the ones they feed on). The caterpillar above is not on a pipevine.

On the same day we also saw this little butterfly.

bordered patch butterflybordered patch butterfly

This is the adult of the bordered patch (Chlosyne lacinia). In some books it might be called a lacinia checkerspot. This little guy is really quite battered.

The bordered patch species is also quite variable in color, like the caterpillars of the pipevine. The North American Butterfly Association has a page of photographs of members of this species. You will see this dark color version towards the bottom. How did anyone ever figure out they were all the same species?

I was not surprised to learn the bordered patch caterpillars feed on sunflowers (as well as ragweed). Here is the garden that was only a few feet away from where I found the butterfly. If you want to raise butterflies, just plant a few of these.

sunflower garden

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I often get questions about how to raise caterpillars. One of my first jobs during college was raising caterpillars, which lead to similar jobs throughout the years. Why raise a caterpillar? Not only does successfully taking care of another living thing lead to insights into its biology and behavior, but also when a beautiful butterfly or moth emerges, it is an amazing experience.

A few weeks ago I wrote a post about white-lined sphinx moth caterpillars.

whiteline caterpillar

In the update I mentioned that I had placed a caterpillar in a terrarium with moist potting soil (about five inches deep). The caterpillar immediately disappeared, but I knew where it had gone. Large moth caterpillars, like white-lined sphinx moth caterpillars or tomato hornworms, dig into the soil before pupating. Their pupa looks like a dark reddish-brown cigar. Saturday I found the moth sitting on the cloth I had used to cover the terrarium. It had successfully emerged.

Here it is.

whitelined sphinx mothwhitelined sphinx moth

Because white-lined sphinx moths are big and active, they need a lot of nectar to keep them going. After taking a few pictures, I immediately let it go. Here’s a link with some amazing pictures of white-lined sphinx moths. This entire website is full of great information and photographs.

What do you need to raise caterpillars? It does depend on what kind, but here are some general guidelines.

1. Unless you are using a kit that supplies special food, you will need large quantities of fresh plants. And not just any plant, most caterpillars will only take one or a few kinds of plants as food. Once a tiny larva has started eating one kind of plant, they often will refuse to take anything else, even if other members of its species will. A good rule of thumb is only bring home caterpillars that you are absolutely sure you know what they eat, and you have lots of those plants available to feed them. Edit: What white-lined sphinx moth caterpillars eat.

2. Provide a clean, safe container covered with screen or cloth to allow for air circulation. It is best to keep the container outside in as natural conditions as possible. Insect life cycles are extremely sensitive to light and temperature. If you bring the critter inside where it is cool and dark, it may emerge days or even weeks after wild members of its kind and may miss critical windows of opportunity to perform necessary behaviors like mate or migrate.

3. Keep only one or a few in a container. Crowding insects into small containers greatly increases the chances for disease. Insects can get viruses, bacteria and fungi, which can make them sick, just like those things can make humans sick.

Scientists have suggested that monarch butterflies may migrate because of a parasitic infection. This parasite (a protozoan) causes the butterfly to be weak but not die. By going on long migrations, the sick individuals are left behind. When we handle monarchs, we risk spreading the disease even more. Let me know if you’d like more information about this.

4. Provide sticks for butterfly caterpillars to climb on when they are about to make their chrysalises. Moth caterpillars will need plenty of moist soil to dig into. Other caterpillars may like to have different substrates to pupate in, like cloth or egg cartons.

5. Insects are also sensitive to humidity, especially when they are molting. It can be tricky, but try to keep the humidity up without getting the container too moist. Too much humidity can cause things to get moldy.

I hope these guidelines doesn’t sound too negative. Having a lot of experience, I have a better idea of all the things that can go wrong and I wanted you to avoid the problems. And oh yes  here's one more:  don't leave the lid off the container once the caterpillars have pupated. My son did this, and we had cabbage-looper moths all over the house. (It was actually a hoot!)

One great way to raise caterpillars is to plant butterfly and moth plants in a butterfly garden. (Check out an earlier post on butterfly gardening.) Then the caterpillars do all the work themselves.

Also, don't forget to take a look at some of the butterfly and caterpillars books for children.

And finally, my friend Debbie called again. Her passion vine plants now have gulf fritillary caterpillars on them (see last week’s post for details).
gulf fritillary caterpillar

This week my friend Debbie called and invited me to visit her butterfly garden. Sure enough, when I arrived there were several species of butterflies flitting throughout her yard. By far the most common were the bright orange and silvery white gulf fritillary butterflies. I also saw numerous skippers and a few giant swallowtails, as well as a yellow sulphur butterfly.

It was hard to get the active gulf fritillary butterflies to sit still long enough to get a photo. The adults were searching her yard for the numerous passion vine plants she had planted. The adults lay eggs on the plant and the caterpillars use it for food. Can you guess what happened to this one?

gulf fritillary

Here’s an adult apparently laying eggs on a piece of passion vine. Note the remnant of a chrysalis hanging to the left of the butterfly. Can you see the beautiful silvery-white patches on the undersides of the wings?

gulf fritillary

Debbie’s passion vines are in various stages. Some have no leaves left from all the caterpillars that have been feeding on them in the past. If you are going to have brilliant, vibrant butterflies, you’ll have to accept that your plants may look a bit raggedy. The vines are around an aloe plant in a pot.

passion vines

She has a couple of different passion vines, with different shaped leaves. Here is one that still has leaves.

passion vine leaf

Here’s another with an empty chrysalis.

fritillary chrysalis

The passion vines have gorgeous, very unusual flowers. I couldn’t find flowers this week, but here is one I shot at the National Botanical Garden a few months ago.

passion vine flower

Here is a link for passion vine flower photos of several different species.

I did find a fruit.

passion vine ruit

Debbie opened one and showed me the unusual seeds inside. Cool!

passion vine seed

Here is a cute skipper that was more willing to pose for me than the fritillaries. The skipper caterpillars feed on various grasses and they are quite common. Sometimes they are mistaken for moths because of their drab brown color.

skipper butterfly

This experience made me realize how very rewarding butterfly gardening can be. We were able to see and talk about so much in just a short period of time. With a few well-chosen plants, some sun, water and patience, Debbie has created a lively and enriching environment.

Debbie, thanks for sharing.