Tailing the butterflies

I curbed my fascination with monarch butterflies when the swallowtails showed up. I was standing in a hayfield, the August morning’s harvest of firewood stacked in the trailer. I took my camera and walked into the blooming red clover.

There were half a dozen or more monarchs within my camera range. This was good news, or good views, for several years ago I stood in this same spot and was lucky to see a monarch or two. Are they recovering with our awareness of how much a milkweed plant means to a monarch butterfly? Or was I witnessing the early signs of migration, when monarchs gather in groups and roost by the hundreds in trees.

I’ve seen the roosting once, as a child, in the giant cottonwood tree of our farmyard. There were hundred of monarchs on the trunk and the lower branches on an afternoon in September. I’ve never forgotten the sight, and have not seen it since. But I keep looking.

As impressive is the monarch with wings in varying shades of orange, and white and yellow spots on the black borders, my eye was suddenly captured by an even larger butterfly. The giant and tiger swallowtails (giant swallowtail in photo above) were also probing the red clover, extending their proboscis tubes into the purple sweetness.

At 6 inches, the wingspan of a swallowtail is at least 2 inches wider than a monarch. It also has those tails protruding from the rear wings, which the monarch doesn’t have. And, with yellow and deep brown wings with dots of orange and blue here and there, an argument could be made that the swallowtail is as colorful as the monarch.

But there is one big difference in the two species. The monarchs we see now are the last of two or three generations to hatch in these parts this summer. Monarchs summering on their breeding range will only live a month, give or take a week. That is, except for the last generation we now see in August. These monarchs will live up to 9 months, and they are the ones that will make the incredible flight of nearly 2,000 miles to the forests of central Mexico, where they hibernate.

Unlike birds, overwintering monarchs in Mexico will not return to our northland. They will start out in February, lay eggs in the southern states and then die. Young monarchs will pick up the chase northward.

But the swallowtail will not fly south. Like monarchs, the swallowtails’ life expectancy in our summer midst is short—about a month. This will continue until the last eggs are laid and the swallowtails’ larvae caterpillars emerge. Before frost, those caterpillars will turn into pupas on several types of plants and also tree twigs.

Tiny butterflies overwinter inside the pupa, or chrysalis, with butterflies emerging when the weather warms in spring. It can be a long wait for a monthlong life as a fluttering butterfly.

So I stand in the field of clover, the monarchs and butterflies all about me. In a few weeks, some will fly thousands of miles, others will lay eggs and give up their lives. Now, I am fascinated with swallowtails, too.