Wednesday, September 8, 2010
I adopted a few caterpillars I found on some milkweed around a local pond. I wanted to observe and document their life cycle as I find the metamorphosis so incredible.
After a few weeks of munching on milkweed leaves, the caterpillar attaches itself with very strong web-like strands of silk to a leaf, branch or in my case the top of the terrarium I was using as their home. They hang in the classic "J" shape for about a day and eventually form a thick, green, waxy cocoon with several brilliant gold dots ornamenting the top and sides.
After about 12 days, the chrysalis starts becoming transparent and the butterfly within can be seen more clearly. Right before they are ready to emerge, the chrysalis is paper thin and very brittle.
At last the butterflies drop out of their cramped confines with crumpled wings and very plump bodies. Over the course of the next few hours they hang upside down and pump the fluid from their bodies out to the wings until they become rigid and ready for flight.
Their tiny forks at the end of their legs allow them to cling to any surface easily. In fact, once they were clinging to my finger it was rather hard to get them back onto the plant!
It is pretty easy to tell the male and female monarchs apart as the male has a small black dot on the his wings while the female has slightly thicker wing veins.
Shortly after I took these photos, they both fluttered away up into a tree and then off in search of more nectar to fuel their migration south to Mexico in the next few weeks. There are about 5 generations of monarchs born over the summer and the last of them make the trip all the way south in the fall.
Posted by Kelly S Andrews at Wednesday, September 08, 2010