September 2015: Monarch
Female laying eggs
Who am I?
Ah, now that is a complicated question. Clearly I am a butterfly, but I don't always look like a butterfly. I go through four basic changes starting with an egg, then a caterpillar (larva), then a pupa (chrysalis) and finally become the butterfly you know and love. After my egg is laid it takes about 3 days for me to hatch. I am then a really, really tiny caterpillar. As a caterpillar I will grow and shed my skin in five stages, called instars. At each stage I am getting bigger. The fifth stage, or instar, is the big caterpillar that is ready to form a chrysalis (pupate). It took me 10-14 days to get here. When I am ready to form my chrysalis I will wander around looking for a safe place to hang out for a couple of weeks. When I find my perfect spot I will attach myself with a pad of silk and wriggle and squiggle out of my larval skin and then harden forming a chrysalis. After a couple of weeks hanging around I will emerge as a butterfly. Life as a butterfly can be short -- for 2-5 weeks I will fly around eating nectar and other sweets, mating and laying eggs. Each year there will be five generations of adult Monarchs. I am the fourth. I will lay my eggs in late September and when they hatch the real magic begins.
The fifth generation of adults, sometimes called the "super generation", will live 8-9 months! It will be the arduous task of this generation, my children, to migrate all the way to Mexico, spend the winter there and then migrate back to Texas in the spring. There they will complete their lives by laying eggs and starting the whole process over again.
(Click here to view images of the Monarch life cycle)
What do I eat?
As a larvae or caterpillar I only eat the leaves and stems of plants in the milkweed family. As an adult I eat nectar from flowers, pollinating them along and way, and other sweets like fruit.
What might eat me?
The milkweed I eat as a caterpillar contains poisons (cardiac glycosides) that I collect in my body. The poisons don't make me sick but critters that try to eat me will not be very happy. Still, even as an adult, there a couple of wasps and a few species of birds that will eat me, despite the poison. Most other species will only try once. It is when I am an egg and a young caterpillar that I am most vulnerable. At this stage spiders, wasps, ambush bugs, stink bugs and others will eat me.
Cool reasons why I am the critter of the month!
- Everybody loves me.
- Despite everybody loving me my populations have been declining due to loss of milkweed and overwintering habitat.
- Males have a black spot on the inside of both their hind wings that makes them easy to spot.
- I can sometimes be seen flying in circles, just like vultures, sailing on rising columns of air to save energy.
- I poop ALOT. (My poop is often easier to see than I am.)
- I smell with my antennas.
- I have been to Earth's orbit -- astronauts have raised me on the International Space Station!
For more information visit http://www.monarchwatch.org.
Overwintering monarchs feeding on nectar. (Photo: Alison Bauer, All Rights Reserved)
Monarch Caterpillar and Male Monarch (note the black spot on each hindwing, missing in the females)