Eggs turn tan/brown & never hatch; dying 3rd instars

[applestar]

This year, I'm seeing a lot of eggs that lose their transluscent quality, turn tan/brown, and never hatch. The leaf that they're on dry up.... I realize now I've been bringing inside some of these already dead eggs as well as seeing some healthy (looking) eggs that I've brought inside turn this way.

Has this been discussed? Does anyone know what's causing it? Please point me to the right thread, I've tried searching but haven't been successful except finding some people mentioning the same.

Also, I've had a second death in my 3rd instar container. First one I found last week had turned mushy and literally broke in half as I examined it -- brown liquid spilling out. Yesterday, I found one browned but intact in the bottom of the box. Luckily, there were only 3 in the container at the time, so I took the other two out and isolated them, and gave the container a thorough cleaning. But anyone know why? I've lost them as 1st instars (the count didn't match when counting 2nd instars) but usually, barring accidental deaths, loss after that occurs at 5th instar/chrysalis stage due to Tachnid fly.

Worried about my babies ...

[Mona Miller]

Parasitized by a tiny wasp, disease, defect:

http://www.evansonart.com/monarchdisease.html
Look at "dead egg" pictures

http://www.livemonarch.com/advanced.htm
Eggs turned black but no caterpillars came out. You may have a paracitic wasp...

[applestar]

Thanks Mona. I do have Trichogramma wasps in the garden and I didn't think of them possibly parasitizing the eggs! I have now sorted through and flushed all suspect eggs.
It's been a very wet summer for us. This morning I had 4 inches of water in containers on the patio -- completely unheard of in the middle of August! I think the unusual weather patterns are promoting disease conditions -- I'll just have to be extra vigilant.

[Mona Miller]

Same here with the weather. We've had some dry spells and then we get drowned with water.

[skates4marty]

Hi Mona. Thank you for evansonart link -- I have friends who have seen higher mortality problems this season; have passed along the link.

[Mona Miller]

I've had the same problem with some of my eggs. It seems like this year is the year of the wasp.

[applestar]

On the other hand, even cats collected as 4th and 5th instars have been successfully pupating -- so far (KNOCK ON WOOD!) no tachnid fly doing the ALIEN at J phase. I have 18 lovely green chrysalides right now and expecting one to eclose tomorrow, 10 very hungry 5th instars, a box full of around 30 2nd and 3rd instars.... Busy, busy, busy!

Every year, I run out of milkweed, grow more, and end up RAISING more cats. Today was the first time I brought in stalks without any eggs or cats on them! (Even when I I didn't *think* I did, I ended up with a tiny baby or two ("WHERE did YOU come from!? ) I hope my milkweeds last -- I still have the A. tuberosa clump in the front garden that I haven't raided yet....)

[Mona Miller]

You'll have to borrow some from friends or go looking along the byways.