7/11/14

Raising monarch butterflies from the egg

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No doubt you've heard about the precipitous decline of monarch butterflies, continent-wide.

When I was helping Wingra School with environmental education sessions, we decided to devote one session to butterflies.  Stephanie Robinson ordered painted lady butterflies from Carolina Biological Supply, demonstrating how to raise them.  On another day, the children planted butterfly weed, while parents purchased butterfly weed we supplied to plant at home.


We feel strongly that saving the Monarchs depends on exposing young children to the life cycle of butterflies.  If kids haven't seen and don't understand this miracle, in the future no one will be motivated to do what's necessary to provide food plants and wintering habitat for the monarch.


But ordering live larvae from Carolina Biological supply is expensive.  It costs about $100 for a small number of larvae.  Half the cost comes from just the express shipping.  So we need a local source of butterflies. That's why I'm raising monarchs from the egg.

My new "pets"

I researched Monarchs on the web--there are many informative sites.

I don't think there's an ethical issue, because I'm planning to release any monarchs I produce, and my efforts are intended to benefit the species.  Each monarch lays 100-300 eggs, yet only two need survive to reproduce the parent butterflies.  So if one egg dies in my kitchen... it's just as likely it would have died in the wild.  I'm being careful.

Eggs are quite small, about a millimeter in diameter.  They are cream-colored to light yellow and round, projecting from the undersurface of a leaf.

I found the eggs on July 3 in the prairie at Donald County Park.  I searched about 20 milkweed plants before I found the first egg.  You can scan a plant quite fast, by pushing it over one way to look at the undersides of leaves, then pushing it the other way, to look under leaves on the other side of the main stem.  Though tiny, the eggs are conspicuous.

You do have to differentiate the eggs from the less regular, less symmetrical little clots of dried sap.  As a clincher, you can use a magnifying glass to look for the little ridges on the sides of the egg.  About a day before the egg hatches, you can see the caterpillar's black head through the translucent egg shell, on the end of the egg away from the leaf.

Suspense...

I collected two eggs at the park, by carefully removing the leaf the egg was attached to, and bringing it home.  I placed the two leaves in a large bowl, sprinkled a few drops of water in the bowl, then covered it with a piece of plastic wrap, held on with a rubber band.  I punctured the plastic wrap with a fork.  The idea is to keep the humidity high, so the eggs don't dry out.

I was getting discouraged, because it was taking so long.  Were my eggs dead?  But after four days, I noticed the end of the egg turn black (the head was developing).  The next day, the two little guys had hatched!  They were really tiny, about 2 mm long.  But they were definitely moving about--you could see their progress after 10 minutes.

One even made a tiny hole in the leaf, and left a few tiny pellets of excrement (frass).

The second day, I picked two new leaves from milkweed plants in my yard, because the old leaves were drying out.  There are two ways you can move the caterpillars onto a new leaf (very carefully)!  For one, I cut a tiny triangle out of the old leaf, with the caterpillar sitting on the piece, and moved it onto the new leaf.  For the other, I tapped the old leaf till the caterpillar fell onto the new leaf, dangling from a tiny thread of silk.

Now on their second day after hatching, the two tiny eating machines are starting to make larger holes in the leaves.

I've persuaded two of my neighbors
to plant butterfly weed on their terraces, and given them the plants.  Yesterday, Al Nettleton gave me a large number of surplus butterfly weeds from his garden.  Now I'm beginning to understand what motivated Johnny Appleseed.

Stay tuned for more adventures with Monarchs!

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