Cross Posted from Monarch Watch Dplex-L Email list:
From: Debbie AM Jackson
Date: Mon, Sep 10, 2012 at 11:11 PM
Another option that saves feeding adults for a few days but you also need a warm frig or wine cooler (45-50 F):
When the pupae start to turn dark about 4 pm – 9 pm the evening before they would eclose, put them in a sealed plastic container. Cooling the pupae will keep them from eclosing. They still develop, but very slowly so check on them at least twice a day and remove ones that are very dark and appear ready to eclose in minutes. Store for a max of 5 days; the sealed container keeps them from dehydrating in our frost-free frigs. When you are ready for the batch to eclose for your event, take them out of refrigeration the evening before and set them in a container with screening for sides so they can climb up and dry properly. I use a $1 clothes hamper from the dollar store. It’s rectangular and I invert it so the hole is on the bottom, or you can cover the hole with cloth, pin a dishtowel over it... whatever.
For my last tagging event on Sunday, I set all the pupae out late Friday night on paper toweling and covered them with the inverted screened hamper. When I awoke Saturday morning, 70% of them had eclosed and crawled up the sides; the rest continued to eclose all day. All were released Sunday. I could've hand fed all of them, but I had another monarch program to conduct plus a bonfire with friends that evening, so no time. All the monarchs went into envelopes Sunday morning so they'd not flap too much before they got tags and all flew off perfectly after warming in the sun a few minutes. Only 2 pupae did not eclose - they are obviously "sick" and wouldn't have eclosed under normal conditions.
Those of you who do school programs, this works very well. I put the cooled pupae in a stryrofoam cup or screen-lined plastic cup http://monarchwatch.org/forums/viewtopi ... =648#p3241
and set that in a small cooler with a few ice cubes. Make sure it can't tip over, prop your cup with a water bottle or 2. Take the cup out when you arrive, ask a teacher to warm them in the palm of their hand and presto... in about 20-30 minutes your monarch will eclose. At this point we hold the chrysalis by its silk so it hangs naturally. Close monitoring is vital, but everyone holding them is quite attentive. (I only ask for volunteers.)
I wish I'd discovered these techniques years ago. Getting monarchs to eclose on queue takes a little practice; I'd suggest you try it at home first to work out the timing but you'll find, if you have 3-6 ready for your program, you should have at least 1-4 eclosure(s) for all to see. The rest will eclose soon.
flutters, Debbie Jackson (Davisburg, MI)
ps - Sorry this is so long !!