the amazing Monarch
In this area (Ohio) of the country, the season’s last brood of Monarch Butterflies will emerge in late September and early October. It is this generation, on whose shoulders all future generations now rest. Several weeks earlier, our subject began life as an egg, carefully placed on the leaf of a Milkweed plant by his mother. The sticky white sap of the Milkweed is ingested by the Monarch caterpillar as it eats, being mildly toxic and very nauseous, the substance stays with the insect the rest of its life, offering it protection from would-be predators. Milkweed by the way, is the only plant the Monarch will lay her eggs on and the only plant that can support our baby Monarch as it grows.
In order for the larva to keep growing, molting must occur. This happens when the old skin splits, revealing the new skin underneath. Once the caterpillar has wiggled free, it has completed 1 cycle or Instar. This particular caterpillar (or larva) is in the 5th Instar or last stage of the larvae cycle. The last molt is much different than the others. The larva crawls away from its milkweed plant, searching for a suitable perch. It then weaves a silk mat from which to hang. When the mat is complete, the caterpillar grabs the silk with its rear legs and hangs upside down. The front part of its body will curve up to form a "J-shape."
Hours later, a slight color change and a small amount of movement signal the forthcoming event. The skin splits once again, several jerky movements and seconds later the chrysalis or pupa comes into view. The chrysalis is an emerald green coon like, however non-woven structure that will serve as home for the next several weeks. It is at this stage of life where the magic really happens. Once tucked safely inside the chrysalis, the caterpillar's molecular structure is completely broken down and in a true miracle of nature, reassembled again as a completely new creature.
About 24 hours before the Monarch emerges; the chrysalis turns clear, exposing the unmistakably orange and black colors and patterns of our new butterfly. Two things are strikingly apparent has he frees himself from the chrysalis. The abdomen is abnormally swollen and the wings are small and shriveled. Immediately, excess body fluid is pumped from the abdomen through veins in the wings. Watch, and you can see them expand right before your eyes. An hour or so later the wings have dried and our Monarch takes flight, looking for his first meal as a butterfly.
As winter approaches, these tiny creatures must make their way thousands of miles south and west to wintering grounds in California and Mexico. Without the luxury of a road map or someone to guide them, the Monarchs make this amazing trek over prairies, rivers, expressways, and mountain ranges, arriving at a winter home they have never set eyes on before. Here they will gather by the thousands waiting for winter to loosen her grip. And with the onset of spring this same brood will make its way north, populating areas of the United States along the way. As each new generation matures, they push their way farther and farther north. Several generations later, Monarchs can be found as far north as Maine and parts of Canada. Then, in the fall of the year, the last brood is beckoned home and the cycle repeats itself all over again.
Jerry Dalrymple
Nature and wildlife photography
