The Magnificent Monarch Journey

Wouldn’t it be great to be able to fly down South every single winter and enjoy the beautiful warm weather of Mexico and California, all expenses paid? Well, I would definitely think so, and the Monarch butterfly is lucky enough to be able to do this exact thing every year. This simple orange and black butterfly you’ve seen in your garden from time to time and have maybe kept as a pet in a classroom or home makes an extraordinary journey south every year to be able to thrive and survive in the warmer southern climate during our dreary Iowa winters.
This voyage can last up to 3,000 miles for the Monarch butterflies to reach their Southern destination, and no, they don’t get the privilege of using cars, trucks, or planes that we would have. The changes in weather such as cooler temperatures and shorter day length trigger the migration for the butterflies. Astonishingly enough, the butterflies that actually participate in migrating southward have never even made the trip before! They are about two or three generations apart from the last Monarch to make the voyage. Researchers suggest that this trip is made possible every year with the use of a circadian clock located in the antennae of the Monarchs. Another surprising little tidbit of information is that the Monarch butterflies are known to travel to the exact same trees as their ancestors did in previous flights.
The average life span of a Monarch or any adult butterfly typically is not very long, usually about two or three weeks. Now I know that leaves a lot of questioning about how these butterflies can make this extreme trip every year without casualties. The butterflies that make the migration South each year are actually of a later generation as I mentioned above, so they are the exact same as the butterflies that would emerge from their chrysalis in the summertime, except they emerge during the late summer and early fall and reproduce much later during their life. This later generation butterflies gets the “cue” from the changes in weather and scarce food left in their habitat and embark on their trip, but they do not reproduce before this journey. The butterflies that make the Southern expedition can live around 6 to 8 months! After their trip is complete and the winter months are over, the butterflies then reproduce and start their flight north again. While the butterflies that originally made the trip South dies off, they lay their eggs on host plants before they die and later generations finish the trip back up North.
Some, even I, have been known to underestimate the true potential and toughness of the Monarch butterfly. But, the journey they embark on each year is absolutely astounding. They dodge natural predators such as birds, diminishing host plants, and potentially dangerous weather. Next time you see one of these black and orange creatures flying around your garden or even here at Reiman Gardens, think about the true potential of this tiny creature.
By Kelsey Carlson – Entomology Intern
Sources & For More Information:
http://www.learner.org/jnorth/monarch/
http://www.sciencedirect.com.proxy.lib.iastate.edu:2048/science/article/pii/0169534787900553