Approximately 150 butterfly species have been recorded in Ohio, but none are as well-known and beloved as the iconic monarch. The large orange and black butterfly stands out, is easy to recognize, and has a great story to tell.
Monarchs have tied their fortunes completely to milkweed, and that strategy has worked well for most of their existence. Like all species of giant lepidoptera (butterflies and moths), the life cycle of the monarch butterfly is a complete metamorphosis consisting of four acts: egg, caterpillar, pupa, and butterfly.
The colorful caterpillars have evolved the ability to assimilate toxic cardiac glycoside compounds in milkweed. This makes the caterpillar poisonous and deters many predators, including birds, increasing its chances of survival.
Nature: Pokeweed fruit is food for many birds.
Even without human intervention, these insects need all the help they can get. Populations in eastern states such as Ohio make incredible migrations to the oyamel fir forests of central Mexico at the end of the season.
Monarchs born in Columbus must travel approximately 1,800 miles to reach their wintering grounds. It’s in a straight line. In reality, the butterflies end up flying even further, as they have to make a detour around the Gulf of Mexico.
Remarkably, there is evidence to suggest that some monarchs have crossed the Gulf, and have been seen on boats and oil rigs far offshore.
Despite the dangers of such flights, the butterflies still appear on schedule in the Oyamel Fir Forest, usually starting to arrive around the Day of the Dead (November 1st).
The largest roost on record occurred in the winter of 1996-1997, when monarch butterflies covered most of the 45-acre forest that is their primary wintering habitat. Such numbers are inconceivable and it is impossible to estimate individual numbers, so area measurements are carried out. Last winter, the monarchs used only about 2.2 acres in the same area.
As the year comes to an end, the forecast looks gloomy for overwintering monarch butterflies. Everyone I’ve asked, myself included, feels they’ve probably seen far fewer monarchs than in other years.
Despite traveling far and wide on a regular basis, I’ve probably only seen a few dozen, the fewest I can remember. The World Wildlife Fund estimates that the eastern population will decline by 59% this year. There is also a population of Western monarchs. Butterflies that breed west of the Rocky Mountains migrate to wintering grounds in south-central California. Its population has declined by about 95% from its known peak.
As with most declining animals, habitat loss is a big problem. This is especially true in heavily agricultural regions like Ohio. Heavy use of herbicides and the destruction of “weedy” edges and fences are causing milkweed declines.
Urban and suburban sprawl has devastated vast swathes of the monarch butterfly’s former habitat, and increased vehicle traffic has led to a sharp increase in roadkill for the low-flying butterfly.
People can help by planting milkweed, which hosts butterflies, and many do. Even the smallest premises in the suburbs can have butterflies.
Our Metro Parks certainly contribute. I visited Brendon Woods Metro Park on October 6th and took the photos that accompany this column. The monarch had just emerged from its pupa, still drying its wings and preparing for the long flight ahead.
The butterflies were born from planted milkweed plants, and senior naturalist Stephanie West oversees a monarch breeding program that has resulted in large numbers of butterflies.
The disappearance of prolific species like monarch butterflies is alarming. Their loss is an environmental red flag and a slap in the face for how humans treat the environment in which we all live.
On the rare occasion I see a monarch butterfly, I am reminded of the passenger pigeon. It was once the most abundant bird in North America, numbering as many as 5 billion birds. At its peak, no one would have thought that such a prolific animal would become extinct. But various misbehaviors killed the pigeons we killed, and our last bird, Martha, died at the Cincinnati Zoo in 1914. No one alive today has ever seen a passenger pigeon.
Nature: Lincoln sparrows gather in Ohio
Will the once-wealthy monarch follow the same path as the passenger pigeon? It is a great shame for future generations that we can only learn about this wonderful insect through textbooks.
Naturalist Jim McCormack writes a column for the Dispatch on the first and third Sunday of each month. He also writes about nature at jim mccormac.blogspot.com.
