Wednesday, September 3, 2014

Raising Monarchs Part. 2

Monarchs begin with an egg - LB
We recently wrote about Saving Monarchs, the butterfly whose annual migration is in jeopardy.  In the next few blogs Linda Bower will discuss how to raise monarch butterflies, grow milkweed for host plants, and recognize the plants pests.

Got Milkweed? By Linda Bower
We can help the declining monarch population by simply growing milkweed. We can help even more by rearing them in a protected environment. Their natural survival rates are low, with only about 5% surviving to form a chrysalis. The others are killed by a variety of predators, including ants, spiders, true bugs, beetles, and lacewing larvae. Fewer reach adulthood to mate. Now add pesticides, herbicides, traffic and loss of habitat to the equation and its little wonder any monarchs are still with us.

It doesn’t take much time to rear monarch caterpillars, they grow up fast. According to the book, How to Raise Monarch Butterflies, if we grew at the same rate, we would be 30' tall in 2 weeks! With just a little understanding of their life cycle and a little bit of equipment we can make a big difference.

The Egg
Monarch females lay their eggs on the underside of a leaf, usually only one egg per plant. They look like a tiny white bump when first deposited. It will take 4-5 days for them to hatch. You will see a black dot in the egg when they are about ready. Their first meal is the egg case and then they will be still for as long as 24 hours.

Cat heads out - MB
Tight squeeze - MB

When you find an egg on your milkweed, simply place the leaf in a small plastic container with a tight lid. You do not need to punch holes in the container. Line the bottom with a paper towel or coffee filter. You will know when the caterpillar has eaten its first bit of leaf by the hole and frass (poop) left behind.

The Caterpillar 

Caterpillars need to be fed every day for 10-14 days. Cut the old leaf around the caterpillar and place it on top of a fresh leaf. Caterpillars have 6 pairs of eyes, but poor vision. They can still find the fresh leaves you place in the container, you don’t need to intervene. Also replace the paper daily as the frass will be plentiful and must be removed to avoid mold.
View from the top - MB
Hiding under leaf - MB

Brother, where art thou?

They eat voraciously during the last few days, so watch carefully. An average caterpillar will devour 20-30 leaves. When it is ready to form a chrysalis, the plump caterpillar will go to the top of the container, spin a patch of silk and attach by its rear end via a support hook and hang down in the shape of a “J” for around 18 hours. Lining the lid with a paper towel or coffee filter will make it easy to move the chrysalis to a netted container where the adult will be able to emerge safely.

Later instar - LB
The Chrysalis
It usually takes 15-20 hours for the new chrysalis skin to harden. Even a blowing leaf can slice into it at this point, so do not touch it! Once the chrysalis is formed it will take 1-2 weeks for the adult to emerge. You can tell a monarch’s gender by examining the chrysalis. Look near the support hook (cremaster) and you will see paired black dots. Females have a vertical line in the segment below the paired dots.

The chrysalis - CB
Emerging from chrysalis
When the monarch emerges, it will take about two hours for the wings to unfold and harden. If it falls during this time the wings will be damaged and it will not be able to fly. It is ready to release when it begins flapping its wings. Just let it go! Monarchs that emerge in late summer are no longer mating but concentrate on fattening up on nectar for their migration. Those born in early to mid-summer don’t migrate; they live 2-6 weeks to mate and lay eggs.

Grown and ready to mate - CB
These instructions are printable in this PDF.
Answers to many monarch questions are at

Visit for more information or for troubleshooting if death occurs at any stage.
Photographs by Linda Bower (LB), Mark Bower (MB) and Chris Barnhart (CB)

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