Entomology (Study of Bugs)/Silkworm moths


Hello Sue...
  I've been raising silkworms (cecropia, luna, polys, promethia) on & off for close to 40 years.   This summer has been the strangest ever.   I live in the Chicago area. Typically, the adults emerge in mid-June.  This year has been completely off that schedule. I've seen adult lunas (typically unusual around here) in June, July, and August. I understand sometimes Lunas double-brood, but was also under the impression that I'm too far north for that. ...found Imperials in early July & late August. Found a poly caterpillar around Aug 10th, it pupated (normal 'schedule' for this region)shortly after, and emerged this past Saturday (Aug 30!!).  Even if it does mate, any food for the caterpillars will be dieing/dead by the time they mature. This seems highly unusual.  
 Any idea why the 'schedule' is so messed up?  
  Also...I've raised caterpillars dozens of times before. This year I had fertile Luna, prometheus, and imperial(first time)females.  From approx 350 hatchlings, I had *zero* cats survive past the first week.  They simply didn't seem to want to feed, shriveled & died. I had them in a small container w/ 3-4 types of leaves to see their preferred food, some of the promethea nibbled at walnut (no surprise there), then stopped. My success rate in the past has been around 50% or so, I'd like to think I know how to do this.
Ever seen this happen?
Ron K

I've had problems with inbreeding when keeping the same eggs and solved it by getting fresh eggs from an outside source and crossing my strain with theirs.  After many generations of inbreeding, I started getting shrivel up and die problems.

Did you check for pesticides on leaves?

Did you install new windows in the house with low-e coating that influences the color and strength of the daylight in the house, or did you switch from incandescent to fluorescent or LED lights?  

Entomology (Study of Bugs)

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Sue Kayton


Silkworm expert. Have raised them as a hobby for 20 years. I do not identify unknown insects.

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