With the changing of the seasons, Monarch butterflies migrate by the millions to the exact same wintering grounds along the northern coasts of California and Mexico. However, no individual completes the entire voyage. This journey takes place over the lifespan of three to four generations, requiring monarchs to use cues from the position of the sun along the horizon and their circadian rhythm, or internal clock, to help them navigate their way. It is no surprise that the magnificent Monarch reigns supreme when they are the only North American species of butterfly to migrate north and south each year, and are also one of the few insects that can cross the Atlantic Ocean.
Before monarchs sport their signature vibrant orange wings bordered in black and dappled with white spots, they must survive as a humble caterpillar.Beginning as eggs and hatching as larvae, the monarch survives off of the plant, milkweed. The voracious, plump caterpillars are protected from predators because of their coloring. The caterpillars are banded with yellow, black and white stripes, warning birds and other animals that they poisonous and distasteful. Unfortunately, after the caterpillars have encased themselves in a cocoon they may fall victim to a bird searching for a meal. Hungry birds will taste test different cocoons until they find the least unsavory one of the bunch. Butterflies that survive hibernation and reemerge near the end of summer and early fall must prepare for the long migration ahead of them.
The monarchs that survive the long flight mate anytime between early spring and late summer. Courtship is a dazzling affair, and takes place in two phases. Wooing starts with an aerial dance between a male and female, but eventually the pair will land and remain connected for about thirty to sixty minutes. Larvae that hatch at the end of mating season tend to have a longer lifespan in order to travel south for the winter.
Even though they return to the same wintering areas, Monarchs can be found in a variety of habitats, such as fields, meadows, conifer groves, gardens, and even some urban areas. Monarchs that visit northern California are often found clustered in eucalyptus trees in Santa Cruz and Pacific Grove near Monterey. They have also been observed resting in the tall Eucalyptus trees of the Richmond Field Station, where The Watershed Project’s office is located.These large Monarch gatherings protect the butterflies from cold and rain during the winter.
Currently, this species is listed as near threatened due to a loss of wintering habitats in places such as Mexico, and because changing weather caused by climate change has made Monarchs more vulnerable as they migrate south each year. You can help provide more habitat by planting a butterfly friendly garden in your own backyard, so that this majestic butterfly can continue to amaze us with their beauty and resilience.