I bought an aster that had a nice cluster of eggs that I thought were Pearl Crescents. Well, I found out that they were some type of moth and I couldn't identify them--I tried. http://s964.photobucket.com/albums/ae121/Runmede/Moth/
Here's a photo.
I decided to take the Asters out of the predator proof cage and placed them into my garden in their pots. Well, the wasp are having a field day--munch, munch, munch.
The success rate in the wild is about 1-2%. But, over time the Monarchs just keep multiplying that. Two make it out of say 600 eggs, then those two have two--it does add up. There's still a lot of predation in my yard this year. I have never seen so many wheel bugs (assassins--huge), I think it has to do with the level of Marmorated Stink bugs and the Stink bugs are drawing in more predators. Of course, the predators eat more than just the Stink bugs.http://www.hiltonpond.org/thisweek030901.html
This website has some good pictures and info on the Wheel Bugs
Your caterpillars sound like they have some type of parasite. Probably fly or wasp parasite. The fly/wasp larvae can actually manipulate the nervous system (inside) of the its prey. This causes the caterpillar to take a shorter time or a longer time to pupate. Some times they will go to pupate and just hang there and you can find the string or hole where the parasite escaped. Other times, they will pupate and the string or hole will be in the chrysalis.http://www.monarchwatch.org/biology/index.htm
Monarch Watch Biology
Look on the left for all kinds of good information.http://www.evansonart.com/monarchdisease.html
Great info on everything from rearing to disease.http://www.mymonarchguide.com/2007/07/d ... spore.htmlhttp://www.learnaboutmonarchs.com/learn ... spore.html
OEhttp://www.mymonarchguide.com/2008/01/d ... d-fly.html
Dreaded Tachinid Flyhttp://www.uga.edu/monarchparasites/whatisOE/index.html
How to tell if butterflies are infected with OE
"An infected pupa may develop dark spots or blotches two or three days before the butterfly emerges. These abnormal dark areas are parasite spores. Spores form on the eyes, antennae, wing veins, but mostly on the abdomen. You can see the spores through the outside layer of the pupa a day or two before pigments that color the butterfly normally darken the pupa. Before a butterfly emerges from the chrysalis, pigments are laid down coloring the scales that cover the butterfly. This normal change in the color of the pupa is symmetrical. The color change of an infected monarch happens earlier and does not create a balanced pattern on the pupa."