Monarch Butterfly Mania
The Beginning: It all started on a family hike in July 2007 when Shane said, "Look, a monarch caterpillar!" He was right! He had learned about the life cycle of monarchs in Kindergarten and had just received a book on insects for his 6th birthday from Aunt Angela. And so, the caterpillar came home with us and was the start of a family project. Actually, it became a bit of an obsession. At times, I sacrificed sleep in order to get the photos I wanted -- you have to live on the monarch’s schedule. This is a awesome transformation that we would like to share with you.
Milkweed, Eggs & Caterpillars: With a bug collecting container in hand, Shane (photo A), is searching for eggs (photo B), which are about 1mm in length, and young caterpillars on the underside of the milkweed leaves. C1 shows common milkweed in bloom. C2 shows the common milkweed seed pods. C3 is tropical milkweed, which is an annual when grown in Pennsylvania. Butterfly milkweed flowers and seed pods are shown in C4. Because monarch caterpillars eat only milkweed and the eggs are laid on milkweed our quest for more food led to acquiring more caterpillars. When we find an egg or small caterpillar, we usually take the whole leave to avoid injury to the egg or larva. The recently hatched larva in photo D is actually 1/8" long, which is too small to touch! Caterpillars that are 1" or longer can be handled safely.
Housing: In 2007 we housed the monarchs in our old plastic aquarium (photos E left). At first they shared their space with a woolly bear, who was a fast-moving caterpillar that dined on my daylily leaves, but then we moved Mr. Woolly to his own container so that Shane could play with him without disturbing the monarchs. You could house the monarchs in a jar with holes punched in the top or in a plastic container like Mr. Woolly’s (photos E right), which has a hole cut out of the lid and a piece of screen taped over it.
In the aquarium I placed 2 glass dishes filled with stones and water. The water level had to be kept below the top layer of stones to prevent accidental drowning of small caterpillars – we learned this the hard way. The stones anchored the leaves or stalks and kept them fresh until devoured. I usually put a leaf or 2 on the bottom of the tank in case someone fell or wandered and needed a snack. If there were large caterpillars, I also placed sticks in the aquarium for chrysalis formation. I anchored each stick in a separate jar with stones or marbles so that it could be removed without disturbing the chrysalis too much.
In 2008 we switched to using 1 container per monarch so that it would be easier to monitor monarch health. Each container is lined with a damp paper towel and given fresh bleached milkweed (soaked in 10% bleach for 20 minutes and then rinsed with plain water). Depending on the amount of frass (caterpillar poop), the containers are cleaned every 1-2 days. Containers are cleaned with 20% bleach.
Shedding the Skin: Normally, monarch caterpillars are very busy with eating and growing. Although we haven’t put them on the postal scale, they appear to double in size every 12 hours. Long periods of rest signal that either the caterpillar is sick or that it is about to shed it skin, which it will do 5 times. In one instance, we had 7 larvae of various ages, 5 of which had been introduced the previous day. For several hours no one ate anything and I was getting concerned that they were all sick. To my relief and surprise, they were all about to shed their skins! In photo F1 the face capsule is still attached and the skin is halfway off. In photo F2 the face capsule has been shed. Notice the yellow head. In F3 the larva is shaking his butt to get the skin off. 30 minutes later the black stripes on the head have started to appear in photo F4.
2 Weeks/2 Inches: After the caterpillar reaches about 2” long (photo G), which is around 2 weeks of age, it’s soon time for it to pupate. Instead of eating, they tend to wander about the aquarium, often walking on the lid or on the stick (if one is provided). Sometimes they spin lots of silk on the side of the aquarium. Then they might go back to eating for a little while before deciding where to spin the final silk pad.
The J: It starts with the larva spinning the final silk pad (photo H1, note arrow). Eventually he will hang in the shape of a "J" (photo H2) from this pad by his last pair of prolegs. Most of our larvae hung in the J formation for 12-15 hours before pupating, although one hung for 24 hours. Shane and Joel helped with recording the times that the larvae started their J formation, so I would have an idea of when I needed to be ready to photograph the change to the pupal stage. In photo H3 you can see that the larva’s tentacles are rounded and have some rigidity. You will also begin to notice the green pupa underneather the skin (photo H4 arrow). About an hour before the larva is about to pupate, the tentacles (photos H2 and H4) will wilt.
The Pupal Stage: A larva shedding its skin is interesting, but the transformation to the pupal stage (chrysalis) leaves you in awe! After the tentacles (sometimes called antennaes, but tentacles is scientifically correct) have wilted as discussed above, the larva may wiggle around, the mouth parts will move and it will begin to push its skin towards the last pair of prolegs. Then it will hang straight and the skin will split near the head (photo I1). If all goes perfectly, it will take about a minute for the skin to be completely shed from the pupa (photos I1-4), which will hook its cremaster (photo I4 arrow) into the silk pad.
Of course, larvae do not always attach themselves to the most ideal surfaces. After several hours, the new chrysalis is dry enough to move. To do this, carefully scrap it off the surface (photo J1) with an exacto knife and then glue it to a stick with a super glue or a thick craft glue. The easiest method is to tie it by the cremaster (photo J2) and then scrap it off and tie it to a stick (photo J3) or screen (if you have made an emerging cage). You can also do this if you want to weigh the chrysalis periodically as the butterfly develops. The chrysalis needs to hang vertically for the butterfly to develop properly, so do not spend too much time weighing it.
The chrysalis (photo K) is one of God’s works of art! It is a delicate jade green with metallic gold and black accents. You can see where the wings will form. The head of the butterfly is at the bottom and the abdomen at the top. If all goes well, in 10-14 days the butterfly will be ready to eclose (emerge).
Eclosion of the Monarch Butterfly: Watching the butterfly eclose from the chrysalis and unfold its wings is every bit as amazing as watching the chrysalis form. L1 was taken at 9 days at 12:50pm. The rest of the photos were taken on day 10. L2 was taken 12 hours later at 12:57am after I got home from work. By the time I got up, the chrysalis was even clearer at 9:16am. By 1:15pm I noticed a ridge had formed (photo L4 arrow). At 2:36pm I noticed that a second ridge had formed (photo L5 arrow). This second ridge has not occurred in all of our crysalises. When I checked on the butterfly 10 minutes later, he was coming out of the chrysalis and I barely had time to grab the camera (photo L6).
Even after the butterfly ecloses, it will be 3-4 hours before he is fully dry. The butterfly needs to stretch his wings (photo M1) while hanging onto something rough. If the butterfly is unable to hang and let his wings dry, then they will dry folded and he will not be able to fly. We came up with 2 quick emerging cages, which prevent our guests from flying around the house and getting into trouble with our cats. The first is a large snack container (photo M2) with a piece of burlap (screen material also works well) dangling inside the container and a piece of nylon mesh over the opening. The second is a mesh shower tote (photo M3) I found at the drugstore on sale for $3. Either of these containers can be disinfected if the butterfly is infected with Ophryocystis elektroscirrha (more on this in a moment). I also dispose of any sticks after one use to prevent potential spread of parasites. If we are unable to release the butterfly within 6-8 hours, we also provide fresh flowers and/or a sponge soaked with fruit juice (photo M2). The local butterfly house also feeds their butterflies mashed banana or melon.
Diseases and Parasites: It is worth reading about the diseases and parasites that plague monarchs if you intend to try raising them yourself. You can visit the webpage links at the bottom of the page for more detailed reading. Some of the problems we have encountered include the following:
- Ophryocystis elektroscirrha or Oe is a microscopic parasite that is the arch enemy of monarchs. The dark brown coloration on the chrysalis in photo N1 started to occur on day 9. After reading on the web I realized that it was infected with Oe and destroyed it. I have noticed the spots occurring as early as the beginning of the 2nd week. Oe (see arrow in photo O, shown next to a butterfly scale at 400x) could be responsible for some of these other problems, but they could also be caused by diseases, viruses or other parasites.
- Stop eating and die.
- Turn black and die.
- Our most frequent problem has been the failure of the larva to fully pupate as shown in photo N2. This fellow got stuck at this point, oozed green juice and died. They do not always ooze juice. After we started bleaching our milkweed, we had less problem with this.
- Parasitoids are another problem. In this case, the monarch larva becomes host to the larva of a fly or wasp. One night I came home to find a caterpillar hanging from the back of a leaf by his prolegs. Brown spots (photo N3 arrow, incidently this is not the caterpillar in the story) had developed on his body. I snipped the leaf and moved him to a jar. After doing some kitchen tasks I came back to find a yellow pupa wriggling out of the monarch carcass. It was just like a sci-fi flick! I was horrified and destroyed it. Usually the fly pupas come out of the pupating monarch larva, but we have had one that came out of a chrysalis (photo N6, see depression in chrysalis). The fly pupa is off white at first and then 24 hours later it becomes dark brown. Wasps, on the other hand, usually hatch and come out of the monarch chrysalis.
- In one instance we had a larva hang in J formation for 24 hours and then it took him about 45 minutes to pupate. The chrysalis finally dried to the shape shown in N4. Eventually the chrysalis developed brown spots as shown in N1 and it started to fill with brown fluid instead of a butterfly.
- When our butterflies first started to emerge, we noticed that they seemed to have two proboscises (photo N5 arrows). I wasn’t sure if this was a mutation or a result of the Oe. I was concerned and contacted biologist Karen Oberhauser, who specializes in monarchs. She said that it is normal for the proboscis to be split, but that it should fuse together shortly after the butterfly ecloses. If the butterfly is weak or infected with Oe, it may not fuse together.
Determining the Sex of Monarch Butterflies: The easiest way to tell the sexes apart is to look at the inside of the wings. The male (P1) has thin veins and scent spots (black spots) on both lower wings. The female (P2) has thick veins.
Our Monarch Studies
Starting in 2008, we decided to approach raising monarchs in a more scientific way. Butterflies are checked for Oe with a microscope (Celestron 44340) before releasing them, and record all of our data on Excel spreadsheets. The data is then submitted to the Monarch Larva Monitoring Project (MLMP) website.
2008 Monarch Study: click to check out our general rearing data and procedures for the study. Some changes from 2007 are that we bleached the containers with 20% bleach instead of 10% and we limited the monarchs per container to 3 (for most of our study we kept 1 per container). We did notice that the butterflies were best released the day following eclosion, as they were strong enough (and quite eager) to fly away. If they were released the day of eclosion, they usually just wanted to fly a short distance to hang. We wanted to know the average days of each stage, and here is what we found:
| Stage | Number of Monarchs Studied |
Average Days for Stage |
| Egg: Collection to Hatching | 43 | 2.4 |
| 1st Instar | 40 | 2.9 |
| 2nd Instar | 51 | 2.2 |
| 3rd Instar | 53 | 2.3 |
| 4th Instar | 56 | 2.7 |
| 5th Instar | 51 | 4.9 |
| Hatch Date to Pupa Formation | 34 | 15 |
| Pupa Formation to Eclosion | 41 | 10.7 |
| Hatch Date to Eclosion | 25 | 25.9 |
2009 Monarch Study: Our 2009 study is already underway and you can check out the current status. One of the things we are trying to do is grow more milkweed in our yard. Some has been started from seed. We are also trying to grow common milkweed from cuttings (shown below).
 | Blog: I've merged my Monarch Journal with In the News to form a Blog page. Eventually this page may be interactive. |
Monarch Websites
These websites will give you more information on monarchs and clicking on the link will open a new window with Java script.
Monarch Watch. Extensive biological information on monarchs. You can purchase caterpillars from them. We get our tagging kits through this group.
Monarch Larva Monitoring Project. We participate in this watch program. It also has a great Links page.
Monarch Parasites.org Lots of info on monarch diseases. They also have a monarch watch program.
Butterfly Encounters A great source for a variety of milkweed seeds.
Butterflybushes.com. You can purchase eggs and caterpillars from this website. I have purchased milkweed plants from them. You may want to order early, as they usually sell out quickly.
NY Site. More info on monarchs.
Texdr's Blog Follow the story of raising monarchs and butterfly gardening in Texas. Lovely photos.