Saturday, May 5, 2012

The Great Painted Lady Project

One of our common but elusive local butterflies I haven't acquired a photo of to date is the Painted Lady (Vanessa cardui). An elementary school teacher I know happened to have some extra butterfly kits left over from his class, so I decided to adopt three of the caterpillars and try to raise them to adulthood. The larvae go through five stages of growth or instars, shedding their skins between each stage. I guessed (correctly, as it turned out) that the caterpillars in the following photo are third instar.

A closeup of one of the third instar caterpillars.

One week and two molts later, the caterpillars have climbed as high as they can and have attached themselves to the top of the container upside-down. The two on the left are preparing to shed their larval exoskeletons, the third on the right has made the change to a chrysalis.

A closeup of the chrysalis. The profiles of the butterfly's head with eyes and antennae, the thorax and wings, and the abdomen are clearly visible on the surface of the pupal integument. The cast-off larval skin is visible to the upper left of the chrysalis. The adult or imago should emerge in seven to ten days.

And that's where things stand as of today. One of the caterpillars died during its final molt, but with a little luck and vigilance, I'll be able to capture a sequence of images of a butterfly emerging from one of the remaining two pupae.


Maybe it was all the good nutrition, or tender loving care ... the first Painted Lady came into the world early after spending only five days as a pupa, and as a result I missed a chance to take photos of its emergence. I noticed the colors of the butterfly's wings could be seen inside the chrysalis early in the morning, when I came home four hours later, I found this ...

The wings had already hardened enough that the insect was capable of weak flight, here it is, still indoors, perching on my hand.

After having its picture taken outdoors in the sunlight the Painted Lady was released to fly free and fend for itself.

One chrysalis remaining – this is how it appeared at five days ...

... six days ...

... and seven days. The chrysalis was moved outdoors at six days, and recalling my lost opportunity to take photos of the other butterfly, I kept a close watch on the pupa all day. But – no luck, nature has its own schedules and timetables, and for whatever reason, the Painted Lady didn't emerge.

After four hours of close observation the following morning I decided to take a quick break and grab a bite to eat. When I went back outside to check on the chrysalis fifteen minutes later ... you guessed it ... too late! The Painted Lady had broken out in that short span of time, and although the wings were still like rags, weak and floppy, they had already expanded to their full size.

Now here's something that can't be observed in an adult butterfly – the slender, hollow proboscis actually consists of two sections which join at a seam along their length.

An underside view ... the split in the proboscis can be seen if the image is enlarged.

It would be virtually impossible to capture a view of the undersides of the wings when fully opened in a wild butterfly. The red fluid being expelled from the abdomen is called meconium – it's metabolic waste left over from the process of pupation.

Although the wings and body were still soft and tender, within about an hour the Painted Lady was ready to fly short distances. Like its sibling, it was photographed and left to its own devices. I didn't get the photos I wanted, but I did get pictures of this beautiful insect in mint condition, something one seldom stumbles across in the world of nature ... it's a hard, hard struggle for survival out there ...