Monarch Butterfly
Diseases & Parasites

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Monarch Artwork from Evanson Art & Design

Identification Bookmark

Monarch Identification Bookmark/Chart
This 2-sided chart can be used to identify the sex of adult butterflies, the instar stages of caterpillars and to help find monarch eggs. Available on this website and Art Fire.

Monarch Butterfly

Monarch Butterfly Posters & Photos
Several monarch butterfly photos are available as posters and giclee photos on this website, Fine Art America, and Art Fire.

Metamorphosis Poster

Monarch Butterfly Metamorphosis Poster
This educational poster includes 33 photos with commentary that highlight the differences between the sexes, an example of common milkweed, a monarch egg hatching, a caterpillar shedding its skin, the 5 instar stages, a caterpillar changing to a chrysalis, the changes in the chrysalis, and the butterfly emerging. Great for butterfly buffs. Perfect for teachers, especially if you raise monarchs in your classroom. Various sizes are available on this website, Art Fire, Cafe Press, and Fine Art America.

Shane’s Monarch Book 2nd Edition

Shane’s Monarch Book, 2nd Edition
My son loves small books and he wanted a picture book of the monarchs. So I made one ACEO sized. This 14 page book has photos showing the metamorphosis cycle. I let Shane help pick the photos, so some are different from the poster. 2.5"x3.5". Available on this website and Art Fire.

 

 

If you click on the photo plates below, a window will open so you can see a larger view of each photo plate.

Having problems raising healthy butterflies? You are not alone! This page was born out of our frustration! Been there, done that . . . It drove me to the internet to find the answers and I found them in the webpage links at the bottom of the page. It is estimated that only 10% of monarch eggs in the wild make it to butterflies. However, as Voltaire pointed out in Candide, this is not the best of all posssible worlds. Sometimes there are no answers other than this monarch was not meant to be. Keep in mind that these creatures cannot tolerate temperature extremes and they require some humidity. They can also be poisoned -- so only use non-toxic, mild soap solutions instead of insecticides on the milkweed in your garden (I remove aphids by hand or with a stream of water). Also, if you carefully bleach your milkweed and keep the containers clean, it will definitely help you avoid some of the issues below. If you have a sick larva, remove it immediately. It should be isolated or destroyed. Then bleach the infected container and give any remaining monarchs a clean container and new food and a fresh paper towel. Also wash your hands or change your rubber gloves between handling different containers.

Dead Monarch Egg vs. Live Egg

Dead Eggs

The egg in A1 is a healthy egg that was just laid. A2 is close to hatching. You can see the head (black spot) of the monach near the top of the egg. In A3 the larva died and you can see the head is near the bottom and the top of the egg is empty. A4 is a dead egg that has turned deep yellow. Most likely this egg is infertile. A collapsed solid egg would also be infertile. A5 the dead egg has turned black. Could have been disease. Could have been a congential defect. I have read the egg could also be host to a wasp egg/larva. I have seen several of these during the summer of 2010 and may try to raise the next one I find to see if there is a wasp inside. If you use a mesh or wire cage outside, keep in mind that thrips and lacewings will eat the monarch eggs if they can get into the cage. A lacewing will leave an empty shell with 1-2 punchure marks (A6), which I have seen numerous times.

Parasitoids: Wasps and Tachinid Flies

Tachinid Fly

Parasitoids are a problem with larvae, especially 4th and 5th instars. In this case, the monarch larva becomes host to the larva of a fly or wasp. But, as we have experienced, if you get a fly in the house, your larvae can become victims during cleaning time. In any case, the first time I witnessed a fly vicitim, I came home one night to find a caterpillar hanging from the back of a leaf by his prolegs. Brown spots (photo B1, 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. Most of our fly pupas have come out of chrysalises (photo B2, see depression in chrysalis). The fly pupa is off white at first and then 24 hours later it becomes dark brown. Incidentally, Shane was eager to collect monarchs during the spring of 2010, but we couldn’t find any. So he found 5 tent caterpillars and raised them. 3 of the 5 were victims of flies. 2 of the larvae became moths.

Wasps, which we have not encountered yet, usually hatch and come out of the monarch chrysalis.

 

Bacteria, Viruses, Fungi and Protozoan

Monarch Diseases

Monarchs and other butterflies/moths are suseptable to diseases, viruses, bacterial infection and protozoan. You should make sure you are using 20% bleach when you clean-- disinfectant wipes may be bleach free. While these problems are frustrating if you are trying to raise butterflies and moths, they are necessary in nature to keep population growth in check. Some of these are used as organic insecticides.

Oe in Monarch Butterflies

Ophryocystis elektroscirrha or Oe is a microscopic protozoan parasite that is the arch enemy of monarchs. It can also infect queen butterflies. Bleach is currently the only reasonable thing that kills it (unless you can put your equipment in an autoclave). Before we release our butterflies, I check for Oe (see the red circles in D1 and D2, shown next to butterfly scales at 400x) with our Celestron 44340 microscope. The affects of Oe can be seen in photos D3-D11.

The spots on the chrysalis in photo D3 appeared during the second week. After reading on the web I realized that it wasinfected with Oe and destroyed it.

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 D4. Eventually the chrysalis developed brown spots as shown in D5 and it started to fill with brown fluid instead of a butterfly. It may also have had NPV.

To date, the attempt at a chrysalis in D6 is our most bizzare pupa. We have had 4 such pupas. Just the stuff sci-fi is inspired by!

Photos D7-D9 show problems with emerging. In D7 the butterfly’s butt is stuck in the chrysalis. In D8 the chrysalis opened at the wrong spot. In D9 the butterfly’s head is stuck in the chrysalis. My helping to "free" these guys was no help at all. At the time I didn’t realize that Oe was the problem. Now, I just detroy them instead of letting the poor things struggle.

When our butterflies first started to emerge, we noticed that they seemed to have two proboscises (photo D10). I wasn’t sure if this was a mutation or a result of the Oe. I was concerned and contacted by 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.

If the butterfly has Oe or is weak it may not be strong enough to hang on to the chrysalis, stick or container and it will fall while drying its wings. This could also happen accidentally. Unfortunately, when the wings dry all crumpled up as shown in D11, the butterfly will not be able to fly. If it was an accident and the buttefly is able feed, you could keep it as a pet as long as it has food that it can reach. However, virtually all of the ones that have fallen that we have had, have been infected with Oe or were too weak from another pathogen to feed.

 

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© 2009 Valerie Evanson. Unless specified otherwise, all artwork is copyrighted by Valerie Evanson.