Raising Monarchs, 2019
From Caterpillar to Chrysalis
March 22, 2020

  Approximately ten days after hatching, a monarch caterpillar has eaten its fill and is ready to go walk-about. If outdoors, the caterpillar may wander 10 to 30 feet or more in search of a suitable place to prepare for the next phase: becoming a chrysalis.

In a cube or home of its own, the caterpillar will wander back and forth until satisfied. Ideally, its choice will be at the top of the cube.

After the caterpillar has selected its place and excreted an attachment, the caterpillar assumes a J position.

Monarch caterpillar to chrysalis
  The caterpillar remains motionless in its J position for about 24 hours. The first sign of the activity to come is when the antennae become crinkly. (The change in background lighting comes from its being close to sunset for this and the following photos.)
Monarch caterpillar to chrysalis
  Chrysalis formation is imminent when the caterpillar loses its J shape.
Monarch caterpillar to chrysalis
  A monarch caterpillar proceeds to chrysalis by shedding its skin to expose the chrysalis beneath.

You can see the start of the shed by the thin line of green at the bottom.

Monarch caterpillar to chrysalis
  From the moment the skin splitting is first observed, it takes about 2 minutes for the caterpillar to complete its shed.
Monarch caterpillar to chrysalis
  The caterpillar is about halfway there.
Monarch caterpillar to chrysalis
  The caterpillar's skin is pushed upward.
Monarch caterpillar to chrysalis
  Here we have a crucial moment. The chrysalis has formed but the skin is still there.

There is a sense of high drama or suspense while the chrysalis swings wildly back and forth - until the old skin is tossed away.

Monarch caterpillar to chrysalis
  Success! The chrysalis is free from the caterpillar's skin.
Monarch caterpillar to chrysalis
  After a half hour or so, the monarch chrysalis assumes its customary shape. At this early stage it is soft and fragile.
Monarch caterpillar to chrysalis
  After another hour or so, it hardens and becomes recognizable as a typical monarch chrysalis.
Monarch chrysalis
  Note: The above photo shows a chrysalis tied onto a branch.

Moving a chrysalis is occasionally necessary, such as this one that formed its chrysalis on the bottom of a leaf. The leaf had begun to droop, and so relocating the chrysalis to a higher position seemed a good idea.

The next page covers the chrysalis becoming a monarch.

My monarch home page  ||  and Pennsylvania butterfly page

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