The Mighty Monarch Butterfly
As children, we were taught that the “King of the Jungle” is the Lion. But have you ever considered, of all the animals in the animal kingdom, which one might be thought of as the “King (or Queen) of the Sky”? Imagine no further than the delicate and beautiful Monarch butterfly.
These colorful and feather-light insects have a short life-span, yet they are hard-wired to complete the most unimaginably complicated task considering their size – to combine a four-stage life cycle with one of the longest migrations known in the insect world. Let’s take a closer look.
The four stages of the Monarch’s life cycle are:
- Egg
- Larva (Caterpillar)
- Pupa (Chrysalis)
- Imago (Adult butterfly)
One female Monarch can lay 300-1,000 eggs. The eggs are instinctively secured to the underside of milkweed plant leaves and take from three to five days to hatch.
The larva or caterpillar stage takes 10-14 days to complete. Once hatched, the caterpillar eats the remains of its egg before turning its entire focus to the milkweed leaf. This instinctual location for the eggs is because the milkweed plant contains chemicals that, once ingested, make the caterpillars taste unappealing to predators. Since the milkweed leaf is the only food source for the caterpillar, it is crucial that these plants remain preserved in nature and untouched by chemicals. The unpleasant-tasting milkweed chemicals remain in the caterpillar’s body throughout its adult butterfly form.
During the 10-14 day lifespan of the caterpillar, it will shed its skin five times. Each shed is larger than the previous and also takes on a slightly different appearance. On the last shed cycle, the caterpillar enters the next life cycle – the Pupa or Chrysalis stage.
Like the caterpillar stage, the chrysalis stage will last from 10-14 days. During this time, the caterpillar will attach itself to the underside of a leaf or branch using a sticky substance. It will hang upside down and shed its skin to reveal a protective covering, or chrysalis, which is green in color to help camouflage itself. Inside the chrysalis, the caterpillar will metamorphose into its adult form, which is the final stage.
Finally, the chrysalis opens to reveal the adult Monarch butterfly. The butterfly will stretch its wings out to dry, then it is off to feed on a variety of nectar-producing flowers and plants.
Migration
In mid-August, millions of Monarch butterflies will begin migrating from Canada and the northern United States to the warmer southern U.S. and Mexico, where they will stay for the winter. This trek can span over 3,000 miles from Canada to Mexico! The life-span of these southward migrating butterflies is only 8-9 months, in which they will not only have to make the trip but also reproduce in the warmer states so the new generations of butterflies can begin their northward migration in the spring. The new generation reach adulthood in 4-5 days and produce additional generations that will make the northward migration. In March, the new generations of Monarch butterflies migrate northward, however, not every butterfly will make the entire journey, which is why the northward migration occurs in stages and between multiple generations. For this reason, the butterflies in the southern regions reach maturity in 4-5 days and can reproduce many offspring within two to five weeks. The adults die after five weeks, leaving the offspring to make the trip north. Alternately, as previously mentioned, the Monarchs in the north traveling southward for the winter will live 8-9 months, increasing their chances to make it to the south for the next life cycle to begin.
Whenever I see Monarch butterflies, I cannot help but marvel over the journey and endurance of these delicate creatures.
