The monarch butterfly population everywhere has been declining for decades. The tragic loss of this colorful species, lovingly known as mother nature’s children, is due to destruction of its staple diet and habitat, the milkweed plant. Another cause of recent decline is the deadly impact of global warming and climate change.
This year especially, as their usual routes of travel, the absence of monarchs is rapidly becoming in our minds a forgotten cherished seasonal memory that was important to us. The entire life cycle that began with laying a single egg on a milkweed plant followed by weaving and spinning a caddis that shreds into a caterpillar and then a butterfly is illustrated in my drawing.
The female will subsequently lay as many as 300 eggs during her lifetime for this four-stage metamorphosis into summer. Amazingly, the last generation of the season does not reproduce, as being in a suspended state called a “reproductive diapause” that is ended when it is time to begin migrating south.
The migration generations have an enormous task to fly from 2,000 to 3,000 miles to reach the same destination tree forest every year in Mexico. Completion takes four consecutive overlapping generations with each overlapping and traveling farther than the previous one. Science is still trying to discover what directional aids are used and passed on to others.
It appears from research that a main signal of navigation is the reading of magnetic pull of the earth’s gravity, as well as the relative position of the sun as they move along. There is a universal instinct to follow the leaders in a group around them. They also cluster together in direction because of warmth from the coming cold temperatures behind them. Finally, they return to the same branches of an Oyamel tree that attracts thousands of tourists in Mexico to witness this remarkable seasonal spectacle. This formation is called a butterfly colony of migration.
More than 90 percent of North American monarchs have somehow been wiped out over the last 20 years. Adult monarchs feed on the nectar of many types of flowers, but they breed only where milkweed is found. For this reason, it is known as a host plant where the forms of larva can develop into a butterfly.
Several national environmental conservation organizations are working of this phenomenon, including the Environmental Defense Fund, as well as Friends of Wildlife. However, it seems to me that planting a butterfly garden by townships and communities, as well as private homes, would reverse the present exodus of extinction locally. Then the colorful living spirit of the natural world would soon appear traveling right through our own back yards for our own awareness and satisfaction.
By George B. Emmons