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Q:	I have milkweed and monarch crysilsis but the wasp are eating a hole in the crysilis and then they eat the larvae. I have watched them eat two of the pupa already. What can I do to stop them from eating the rest of them. I original had 13 caterpillers, I know two died, two got eaten, I can see two pupa still in tact, I can't find the rest. Is there anything I can do to save the rest?
A:

Last year at this time I had found 40 caterpillars on the milkweed in my backyard. To date this year I have 7 caterpillars. What's going on?

There are many possibilities that would explain why you are seeing fewer caterpillars this year. I don't know where you're located, but here in Minnesota, we had a wet and cool spring. Either of these factors could play a role.

Last year, many females could have found your milkweed and laid eggs on it. Perhaps something has changed with your milkweed or the immediate area around it?

Of course, this could just be due to chance. There are year to year fluctuations in monarch numbers, especially on such a small scale (in this case, your backyard.) Because your backyard is a small subset of the entire range of the monarch, you could see wide fluctuations while the monarch population as a whole is relatively stable. Last year could have been an irregularly high year in your area, while this year (to date) is irregularly low. This is not an exhaustive list of possible factors. There are a host of other variables that could also affect the number of monarchs you?re seeing.

I encourage you to go to the Monarch Larva Monitoring Project's website www.mlmp.org to see if there are people monitoring monarchs in your area. If not, I would recommend you sign up to participate!

can a caterpillar still trasform if it fell off the thing its hanging on when its all ready in its cocoon

If the pupa fell, it is possible that the monarch will still develop into a butterfly. However, there is a possibility that the wings will be crumpled or deformed. When a pupa falls in our lab, we tie thread around the cremaster (the little black "spike" that sticks out the top of the pupa) and then tape the thread to the top of a container. The less time the pupa spends at the bottom of its container, the more likely it is to develop properly.

I live in South Florida. I bought some milkweed plants that had big healthy looking caterpillars. I started out with 12. 7 of them became chrysalis. One of the chrysalis turned black almost immediately and had white string hanging. Another one started turning into a chrystalis but stopped half way. One of our chrystalis became a beautiful monarch that I and my kids happily released. I built a wooden butterfly box with net on the sides and a clear see through plastic in the front. I placed a potted milkweed plant inside the box. The next butterfly came out with crumpled wings and died. All of the remaining chrisalis turned clear (Icould see the wings through) then turned black and died. During this process and before I realized that everything was dying, I found more caterpillars on one of the other milweed plants I had purchased. I brought that plant inside my covered lanai. I did not mingle the second group with the first - other than rotating the same potted milkweed plants in the container. They were in a different container. Of the second batch, only two turned into chrystalis. The others mid formed and died or simply died as caterpillars. I saw this morning that there are eggs on one of the milkweed plants. Could this be a bacterial or viral infection that is on the milkweed plants? And if so, is there a way to disinfect the mildweed plants? What do you suggest I do with the new eggs?

The pupa with the string hanging from it is the result of a parasite: the Tachinid fly. The female flies lay eggs on the monarch caterpillars. When they hatch they burrow inside the caterpillar and eat. Then, when the monarch is ready to pupate (or sometimes just after pupating) the Tachinid fly larva emerges from the monarch, and uses the "string" to get down to the ground. Then the fly larva forms its pupa. In all cases, the monarch pupa dies.

A viral or bacterial infection is definitely a possibility with your other monarchs. I would suggest using a 20% bleach solution (4 parts water to 1 part bleach) to sterilize all of the items that you use to rear monarchs. Then, I would pluck the leaves that have eggs off of the plant and cut the plant down to the ground. Don't use the plant to feed newly hatched larvae. Instead, I would encourage you to find new milkweed and soak it for at least 20 minutes (to get rid of predators like ants, or to remove any pesticide/herbicide residues) before feeding it to caterpillars. The eggs that came from your plants should have new milkweed nearby to encourage the new larvae to move off of the original leaves.

One other suggestion is to reduce the number of larvae per container. In the lab we use either plastic deli containers, which only contain one larva, or a plastic shoe-box sized container which house no more than 10 larvae.

Hopefully, these precautions will increase the number of healthy adults.

Q:	What time of the year, or actually what month, do Monarchs lay their eggs on milkweed in Wisconsin ? I have tons of milkweed in our prairie and wanted to raise some butterflies inside with my daughter this year, but wasn't sure when we needed to go looking for the eggs or caterpillars.
A:	Now is a great time for a monarch search! Generally, early or mid June, and then about a month later in July are the best times to find eggs. This varies depending on when the monarchs return from Mexico. If you're in northern Wisconsin it might be a little later, but right now in the Twin Cities, we're seeing eggs and larvae!

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