Of all the migrating creatures of the planet, few are as interesting as the North American Monarch Butterfly, many of which will travel up to 3000 miles to reach their Mexican destination for winter hibernation…then return in the spring to begin production of several more summer generations of their species in the United States.
Each fall, Monarchs born west of the Rocky Mountains migrate, for the winter months, to California…while those originating east of the Rocky Mountains (those we see moving through our Arkansas River Valley region) will travel deep into Mexican mountain forests. After a winter in Mexico, mating of these “hibernating” Monarchs takes place…and that’s when the long migration back through our region occurs, many of them to the Great Lakes area for egg laying.
As you may remember from your schooling days, the lifecycle of the Monarch consists of four stages…the egg, the larvae (caterpillar), the pupa stage (chrysalis), and then the butterfly. There are actually several different generations hatched each summer in the United States.
Here is the cycle of events for the “Lives of Monarchs” each summer in the United States…
February/March – Hibernating Monarchs awake for mating, then begin their long migration to find a place to lay their eggs.
March/April – Eggs are laid on milkweed plants. It will then take about a month before the beautiful butterfly appears (4 days for eggs to hatch, 2 weeks for caterpillar to grow and attach to leaves or stems, and 10 days for the butterfly to emerge). These Monarchs (the new year’s first generation) will then live for only 4-6 weeks and die after laying eggs to start the next generation’s life cycle.
May/June – Generation two eggs hatch, lay their eggs for generation three, and die.
July/August – Generation three eggs hatch, lay their eggs for generation four, and die.
September/October – Generation four eggs hatch. But one of the things which makes Monarchs so amazing, is that this “generation number four” will not lay eggs just yet. These are the butterflies which will take the long migration back to Mexico (or, for western hatchlings, California), live for six to eight months, then return to begin NEXT year’s generations of Monarchs.
Another amazing fact is that these new butterflies will fly back to the same roosting areas…usually to the same exact trees…in which their great-great-grandparents hibernated a year earlier.
Since migrations of the Monarch are enticed generally by length of day and climate temperatures, those who study them are able to determine a general idea of when the most Monarchs will be seen moving through a specific area during each migration period. In our Arkansas River Valley region, that time period is expected to be between September 24th and October 6th, with the population peaking on around October 2nd.
So get out and see how many beautiful Monarchs you can spot! And, if you’re a parent or teacher and would love to host a very interesting and educational project for your kids, you may want to consider “Monarch Tagging” and/or logging of the butterflies already “tagged”. For more information about this and a host of other interesting information about the Monarch Butterfly, visit MonarchWatch.org.