08/22/2026
As summer comes to a nearing end, the days shorten, and the nights become cooler, something with in these monarch caterpillars is beginning to change. Monarchs enter into a state of reproductive diapause this time of year to start diverting energy and fat reserves to prepare for their migration south to the Oyamel forest, their ancestorial mountain ranges in Mexico. Next spring when they begin to migrate back north, reproduction will restart to breed the next generation.
It is not completely known what triggers this biological change within them, but research has demonstrated it to be a combination of internal biological clocks and environmental cues.
How they navigate back to the same few acres of forest each winter, is an even bigger anomaly in the scientific community. Evidence suggests Monarch butterflies use of earth's magnetic field and the angle of the sun to find their way.
