Saturday, July 24, 2010

pupation in action!

The carrot swallowtail had been in the "sling" position for almost 24 hours and I was starting to worry; I couldn't remember how long it normally took for them to pupate after them slung themselves up, but I don't remember it taking that long.
I was checking on her one more time tonight, and just happened to catch the very beginning of pupation--I've never actually been able to watch it happen before. At first her body was heaving, with each segment pulsing individually from the tail up. Here's a picture from early on; sorry for the low quality but I'm taking pictures in low light through wavy plastic here. But you can see here there are already some color changes.
Then suddenly it looks like the chrysalis just starts growing on the back of her head and starts spreading down her body, and it's not clear until halfway down that her old skin is being pushed off, just like when they molt between instars.
It took a huge about of thrashing and writhing to get the skin to detach from her tail, but the whole process of shedding her skin lasted maybe 60 to 120 seconds. After she was fully pupated she continued to writhe and pulse, and from the time I started watching until she stopped moving was about 20 minutes, and this happened, for the record, around 7 p.m. tonight.
The pupa continued to darken slightly after she finished moving, but last I checked was still green with yellow highlights, despite being on a brown twig with the container sitting on brown paper (the pupa can be either brown or green, depending on the environment).

Meanwhile, the little egg that I brought in a week ago has just molted to instar four already. They grow up so fast!

Monday, July 19, 2010

butterflies

Last summer was a sadly swallowtail-less; I think I just got my parsley out too late. But this year I have babies again. Or rather, I have one newborn and one teenager.
On Friday, my friend C. found two tiny eggs on my dill (although one of them is a dud--you can see right though it) and I found a big, fat third instar caterpillar on my carrots. The caterpillar molted into forth instar that night and into fifth (pictured above) today. You can also see in the picture above that she has completely denuded a sprig of carrot greens. Fifth instar is the last, so she'll be spinning a chrysalis already in the next day or two.

The non-dud egg hatched early Saturday morning, and as of this writing it looks like he might be getting ready to molt into second instar. I am assuming it is a black swallowtail, because that seems the most likely, but she looks much redder than other caterpillars I have known (in my experience they are usually closer to black).
In other butterfly news, I also have loads of cabbage white larvae on my broccoli and kale. I would raise them, too, but cabbage whites are non-native and unlike swallowtails they do serious damage to gardens, so for the past few days I've been picking them off and feeding them to my neighbor's chickens, one of whom now recognizes me and starts pacing the coop making whiny begging noises when she sees me in the garden.