The Orchid Island Monarch Butterfly

With some 450 species of butterflies inhabiting its shores, a concentration among the highest in the world, Taiwan has long enjoyed a reputation as a lepidopterist's paradise. When spring comes, butterflies fill the air, flitting among the flowers and rivalling them in beauty.

Exceptional among all the "gay dancers of the sky" is the Orchid Island monarch butterfly, Troides magellanus, which has earned the title of "the most photogenic of butterflies." The chief reason is the back wings of the male monarch, which, seen against the light, change from their original gold to red, to green, to purple and blue, like a kaleidoscope or a prism in the sun.

"Among all the butterflies in the world, those whose wings change color are few and far between, and then it's most often to just one color," says Ch'en Weishou, a lepidopterist and high school biology teacher, explaining why the Orchid Island monarch butterfly is so precious.

With wings about 15 centimeters long and 10 centimeters wide, the Orchid Island monarch is the largest butterfly on Taiwan. Spreading its wings to glide through the air like a bird, the monarch reminds one of an accomplished ballerina confidently performing on the stage.

"The Orchid Island monarch flies rather slowly, four or five kilometers an hour, about the same speed as a person walks," Ch'en says.

This beautiful butterfly is difficult to find on Taiwan itself. Its home is Orchid Island, part of Taiwan Province but about 40 miles offshore to the southeast.

"Taiwan and Orchid Island belong to different ecological systems," Lu Kuang yang, professor of biology at National Taiwan Normal University, explains. "Taiwan belongs to the East Asian system, like Japan and Korea, while Orchid Island belongs the to the South Asian system, like the Philippines. So Orchid Island has many plants and animals that Taiwan doesn't." Some of the monarchs have, however, appeared at K'enting National Park, at the southern tip of Taiwan, where the climate is similar to Orchid Island's.

On Orchid Island, where the forest meets the shoreland, the melon-leaved birthwort, the special food of the monarch's larva, spreads along the ground and climbs up trees. Nestled inside and chewing on its leaves is the tiny monarch larva, which after one month will move to a bush, a tree, or a nearby weed and begin to form a cocoon.

"It fixes its tail to the branch, spins a thick thread, and wraps the thread around its middle like a rock-climber hanging from a cliff," Ch'en says.

The pupa hibernates in the cocoon for three months awaiting the moment when it can "grow wings and become an immortal," as the ancients said. When the cocoon opens, Cinderella becomes a dazzling princess, and the butterfly begins its month-long life among the flowers.

Most people think butterflies just fly at random; actually, they follow fixed paths and trails.

Butterflies fly along the edge of sunlight and shadow, now right, now left, as the wind blows the branches of trees and the shadows shift. In this way, they avoid the eyes of their enemies, the birds and the bees. Some butterflies develop shortcuts around areas where nectar is plentiful. These shortcuts are called "nectar paths."

The wings of the male are the more beautiful. In the insect world, where males outnumber females, the males are often brightly colored to attract the attention and win the good graces of the females. After mating, the female flies back to her place of birth, the melon-leaved birthwort, and lays her eggs.

Because Taiwan has a warm climate, a varied topography, and abundant flora and sources of nectar, butterflies are plentiful and easy prey for catchers. And the Orchid Island monarch butterfly, with its beautiful coloring, is a prized target. Depredations were particularly severe during the 1960's and '70's, when the price for specimens was high.

"It's said they used to catch over 10,000 monarchs every year back then, on an island just 46 square kilometers large," says Ts'ai Pai-chun, a nature photographer who goes to Orchid Island for pictures. He finds it hard to imagine what it must have been like back in the days when they flourished.

Another reason for the butterfly's decline is the destruction of the birthwort, itself a weak species which is giving way to agricultural development.

In response, the Ministry of Interior's Council of Agriculture has asked Ch'en Wei-shou to study ways of bringing back the Orchid Island monarch butterfly, has prohibiting its capture, and is investigating how to protect the melon-leaved birthwort. The butterfly has been listed as a protected species by international environmental groups, as well.

Whether or not we are simply mending the fold after the sheep are gone, the butterflies themselves have lost their trust in us. Ch'en Wei-shou, who has studied them for over 30 years, has found that the butterflies, who used not to fear man, now fly up high as soon as they see us.

"That is what they have learned from their experience," Ch'en says.

So when the mother butterfly shows her baby butterfly around the nectar paths and teaches it how to avoid its enemies the bees and the birds, she now must add, "Fly up higher, and watch out for bad people."

[Picture Caption]

male female

The Orchid Island monarch suspends itself by a thread from a branch before spinning its cocoon. Pictured is a newly metamorphosed butterfly.

male female.

male female.

The Orchid Island monarch suspends itself by a thread from a branch before spinning its cocoon. Pictured is a newly metamorphosed butterfly.