Over the years I have had many pets in my house. In fact, I have lived with a lot of classes of animalia (but not reptilia, although I hear geckos are fun). I have had fish, birds, cats, dogs and butterflies. The last seems like an odd addition, but they are like temporary pets for a few weeks every year, and they require the same commitment of time and energy for the short time they live with me. The reward is watching them emerge as delicate and colourful insects which I can release in my garden to continue their life cycles. I also know that to some extent, I am helping to preserve butterfly populations.
I was first introduced to hand raising butterflies by my neighbour, Melissa Neely, who had followed the lead of Kellie Scott, a local butterfly and moth enthusiast. Kellie raised Monarch butterflies, but she also raised enormous Cecropia moths in a battery of enclosures in her mudroom. My next door neighbour Melissa raised Monarchs, and later Painted Ladies, Black Swallowtails and Question Marks. I started to learn about host plants, caterpillar identification and the process of pupation. One day while shopping at a local garden centre, I spotted a large green and black striped caterpillar with yellow dots on a fennel plant. I knew immediately it was a Black Swallowtail, and I bought the plant (and some extra fennel from the grocery store), and brought it home. Once the children saw what I had, and the caterpillar transformed into a beautiful butterfly, we were hooked. We named him Heimlich, after the movie A Bug’s Life.
It is not difficult to hand raise common butterflies, but it does take a sharp eye, a deft hand, and constant attention while they are with me for a few weeks. Most butterflies hatch only a few days after eggs are laid, spend 10 days or so as caterpillars, and another 10-14 days in their chrysalises before emerging as adults. Then I release them. The main tricks are knowing how to find eggs, and keeping the caterpillars well stocked with food once they emerge. The bug boxes found at your local dollar store do just fine as homes for the insects, but you will have to place a sheet of paper towel between the box and the lid when the caterpillars are small to prevent them escaping through the air vents.
Our most commonly recognised butterfly, the Monarch, is one of the easiest to raise, given that you have ready access to milkweed, which is the ONLY thing they eat when they are caterpillars. It is very important to recognise that caterpillars eat only leaves from specific plants and will die if not supplied with the correct food. Every species of butterfly requires a different host plant. For details on host plants for butterflies other than the Monarch, see my previous article on The Wild Bluffs website community page, Making Your Home Garden Butterfly Friendly. That being said, there is quite a lot of milkweed available on the edges of city parks, ravines and conservation areas, and rural roads. That is also where you can find the tiny eggs.
Monarch eggs are laid singly on the undersides of milkweed leaves, and are creamy white to pale yellow in colour when fresh. As they are ready to hatch, they turn dark very briefly before the eyelash sized caterpillars emerge. When collecting eggs and leaves for food, you should remove only a few lower leaves from a plant. That way it can continue to grow, flower, and produce seed pods. I have found it very discouraging to discover healthy milkweed plants either torn up by the roots or cut off at the top, which means there will be no reproduction. With the challenges to our local milkweed population due to the invasion of alien swallowwort species (aka dog strangling vine), the last thing we need is people tearing up or cutting the heads off the remaining milkweed!
While small, the caterpillars eat very little, leaving miniscule holes in the leaves, but as the larvae grow larger, they need much more food. One of the ways to ensure that the leaves stay fresh when the caterpillars are tiny is to wrap the freshly cut stem of the leaf in wet paper towel and then in plastic wrap. Add a few drops of water to the paper daily or if it dries. The caterpillars shed their skins four times as they grow. These stages are called ‘instars’. You will find that by the time they are the size of a baby’s finger they will be devouring leaves quickly. If the food leaves become limp and begin to dry, you may have to move the caterpillars to fresh leaves. I do this with a very soft paintbrush, brushing them onto the surface of a new leaf and waiting for them to cling on well before closing the box. Always have a few leaves in reserve in a moistened plastic bag in the frig in case you can’t get out for more. They keep very well this way for up to a week. Check the caterpillars morning and evening to be sure they have enough food.
After about 10 days of eating they will seek a place to hang upside down in a J shape and transform into chrysalises by shedding their skins one more time. I put a few sticks in my butterfly boxes so they can find somewhere to attach themselves. Some of these must be close to horizontal to be effective. Don’t worry if the caterpillars attach to the lid of your container, as that suits them fine too. After another 10 days or so the chrysalises will turn from their jade green colour to a transparent shell though which you can see the adult. That’s the day they will emerge. Stay close, because after emerging and hanging upside down for a couple of hours to pump their wings out and dry them, they will need to be released to find food. Don’t worry if there is a little extra ‘blood’ on the floor of the box, as excess fluid will drip off once they have fully pumped up their wings.
You will know they need to be released when they start flapping their wings and crawling around the lid of the box. Avoid letting them fall down to the bottom, as they may get their wings wet with the leftover fluid, which will slow down their readiness to fly. Their wings must be dry to flutter away. For this reason you should avoid releasing them on rainy days, but if they do emerge, put them in a sheltered place under a bush or tree. They will wait for the weather to turn nice and dry.
As for me, I have already raised several Monarchs this spring, as well as many Question Marks and Eastern Commas. I am still looking on my fennel plants in the garden for Black Swallowtails. Tragically, my friend and neighbour Melissa passed away very suddenly this past winter, and I owe my interest and much of my knowledge about butterflies to her. This summer the people in the neighborhood who loved Melissa will dedicate a new Hackberry tree in Cathedral Bluffs Park to her memory—very appropriate given that Painted Lady butterfly larvae eat Hackberry leaves. Every time I release a butterfly now I think of Melissa, and perhaps this article is one way I can ‘pay it forward’ in her memory, by teaching others to raise butterflies the way she taught me.
Article and Photographs by Catherine Bacque
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