Rickinla,

Since the cats are outside, I would guess that they are being preyed upon by spiders. I had a spider get inside the enclosure and the cat was deflated and limp from the spider. OE spore can also affect them, but I haven't seen that happen outside in my garden, but I have heard of other people seeing this.

I am saddened that the caterpillars are dying in a designated area for aiding them.

Mechelle

There are a lot of things that kill caterpillars. Even monarchs, that are protected by toxic chemicals, fall victim to parasitoid flies, predatory wasps, spiders, disease, and stink bugs. I find that in the caterpillar stage, Three things kill them the most. One is OE ophryocystic electroscirrha) a protozoan parasite. Studies show that in late summer, most adults are infected. If the infection load is heavy enough, caterpillars will start to die. The second is parasitoid flies or tachinid flies. Some studies show that around 25% of monarchs are infected. This will typically affect the pupal (chrysalis) stage. Interestingly enough, one theory about OE is that it offers a benefit to monarchs by preventing parasitoid flies and wasps from using monarchs. The third is predatory stinkbugs. If I see a monarch caterpillar hanging dead from the milkweed, I can usually find a stinkbug nymph close-by. They pierce the cuticle of the caterpillar, inject a venom and enzymes and suck out the contents. Sometimes the victim looks a little deflated or not.

-Elisabeth

Thanks for the info, I'll pass it along.

Thanks for the info, I'll pass it along.