For those of you who have been following the blog this spring, you will recall that Sandra has taken an interest in caterpillars. This is the second most obvious stop in the lifecycle of butterflies and moths. An entomologist's mantra might well be: egg, larva, pupa adult...ommm.
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| Courtesy of ASU Ask a biologist! |
Butterfly eggs are tiny and it takes a real scientist to describe what
goes on inside. As you will see, we are now at least familiar with
such an entomologist. A chrysalis,the pupa phase in the life of a
butterfly, is mysterious. Also, unless you are an astute observer of
nature, a chrysalis may be difficult to find and,once found, would take a
real aficionado to make much sense of it until the butterfly inside is
ready to emerge.
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| A love of Wooly Bears is hard wired in my DNA |
At the other end of the spectrum, if one found the caterpillar of the Cabbage Butterfly, known as the "cabbage worm" crawling in his salad it would almost certainly evoke a degree of hard wired horror.
As caterpillars grow they molt and each successive organism is called an instar. The penultimate instar goes chrysalis, the magic occurs, and the next thing you know, you have an emerging butterfly. Until this week, that is about as far as my knowledge went. Following our trip to Central Oregon, Sandra presented her picture of the caterpillar on the rock near Sparks Lake to a Facebook group dedicated to caterpillars. A few weeks ago this group provided identification for the Oak Tent Caterpillar that we discovered in Klickitat Canyon. In this current instance, a member identified the caterpillars we found wandering on the rocks as that of the Anicia Checkerspot.
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| Edith's Checkerspot Caterpillar wandering. |
If you have been paying careful attention, you will recall that the butterfly in that narrow patch of Lodgepole Pine was Edith's checkerspot. And it was this identification of a related caterpillar that caused me to pose the question: If you find and identify a caterpillar, can you claim the butterfly?
You might ask, "Who was this mysterious guesser who almost got it right?' He was, no less than David James, author of Life Histories of Cascadia Butterflies. Simultaneously Sandra ordered his book from Amazon and I forwarded his identification to our guide on the Trail of Butterflies , Caitlin LaBar, along with the above question...Can I add a new butterfly to my list?
And here is what she wrote back:
So, our new best friend has revealed a bit more about herself and, at the same time, may have made question number 2 moot,
David James, PhD still thinks he has it right. Do us mortals love it when the gods wrestle , or does it scare us a little bit?
Once we received James and Nunnalee's book, a new world of lepidoptery opened up. The first chapter is a must read for those interested in the life cycle of butterflies and provides a detailed account of butterfly eggs and caterpillar development and behavior. The lepidopteran duo provide answers to a couple questions that were lingering, related to observations of monarch caterpillars. With the exception of one blessed afternoon in Jim Monk's backyard, where we saw the caterpillars of the Gulf Fritillary Butterfly devouring his lilikoi vines, the Monarch is are the only species with which we have extensive caterpillar experience. Before I let you go I want to relate one amusing anecdote and a related bit about checkerspot caterpillars.
Monarchs, Gulf Frits and checkerspots are all brushfoots, caterpillars in the family Numphalidae. These butterflies have evolved, modifying their front pair of legs in such a way that they are not used for locomotion, but rather more as sensory organs. In this instance, Drs..James and Nunnalee tell us that in most species of butterfly, the larva stay at home and build their chrysalis in association with the host plant. Brushfoot and swallowtail caterpillars, on the other hand, arbitrarily divide into two groups, those that stay at home and build their chrysalis on or adjacent to the host plant and those that become wanderers.
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| All you ever wanted to know about Edith's Checkerspot, James and Hunnalee |
This explains why those three Edith's Checkerspot caterpillars were traveling over a rock instead of munching on the leaf of an Indian Paintbrush, their favorite host plant. These three had molted into their final instar and were wandering, off on a journey to select a distant site to go chrysalis.
Back in Kailua Kona, Sandra and I have become regular visitors to the Crown Milkweed behind the library. Without getting technical, we have seen monarch caterpillars in different instar stages. And it is the only place we have seen a chrysalis in the wild. I feel a little funny saying it that way, because there is little "wild" about a small, top-shaped, gray cocoon hanging from a branch.
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| A Stay at home monarch goes chrysalis on a crown milkweed branch |
There is a legend within the library staff that a few years ago, a monarch caterpillar made his cocoon on the eaves of the library and the staff were able to watch out the window as it matured and the butterfly emerged.
Well, last winter (it doesn't seem like winter in Hawaii, what with palm trees swaying and caterpillars crawling around) we went down to the library on a Sunday afternoon. While I was looking for a chrysalis, Sandra found a caterpillar on the nearby chain link fence. She said to herself, "Silly caterpillar, don't you know that the good stuff to eat is over there?" So saying that, she plucked the caterpillar from the fence. It wriggled furiously and screamed, "You idiot! Put me down! Don't you know I'm poisonous?" And then she walked a few steps and placed the caterpillar on a milkweed leaf. The poor caterpillar looked skyward with a shrug and said, "Damn! Now I have to start my journey all over again."
And that is the truth about wandering caterpillars.
jeff
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| The hapless monarch on his doomed sojourn. Photo SKG |
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