Iowa’s beautiful butterflies

by Lisa Ralls
Winnebago County Naturalist
In recent years, Monarch butterflies have received a lot of attention, and rightly so, because their numbers have declined so dramatically. But, sometimes we tend to forget that there are other butterflies in Iowa and they, too, have special needs. And, as summer heats up and our prairie flowers begin blooming, now is a wonderful time to catch a glimpse of all of Iowa’s beautiful butterflies.
Altogether, scientists estimate that there are at least 750 species of butterflies in the United States and Canada. Just in Iowa, there have been upwards of 120 different butterfly species reported, with 50 of those being relatively common. So, there are plenty of different kinds of butterflies to observe in our state.
Despite their differences, all butterflies have some similarities. They all undergo a complete metamorphosis, which means that their life cycle involves an egg, a larva (caterpillar), a pupa (chrysalis), and an adult. Caterpillars have chewing mouths and may require a specific host plant (such as Monarch caterpillars that only feed on milkweed plants), or they may be able to feed on a variety of plants. Adults, on the other hand, have straw-like mouths and can only drink nectar and other sweet liquids. They, too, may be more or less selective in their feeding preferences, depending upon the species.
The largest butterflies we typically see in Iowa are the Swallowtails. The Giant Swallowtail (black with pale yellow stripes and spots), and the Tiger Swallowtail (yellow with black stripes) can both have wingspans of over 6”. The Black Swallowtail is slightly smaller, but beautiful with its black color and iridescent blue spots on its back wings.
Some of the more common types of butterflies we see here in Iowa are the Sulfur butterflies. As their name implies, these are small yellow butterflies. Other aptly named butterflies are the Blues, tiny butterflies that come in various shades of blue. Their wingspan rarely exceeds an inch, but they can often be observed around puddles of water or mud.
A strikingly pretty butterfly is the Mourning Cloak, a relatively large butterfly that is all black and deep blue, except for a yellow stripe all along the edge of its wings. Painted Ladies and Painted Beauties look very much alike, mostly orange with black and white spots; Fritillaries are also orange with black spots, but they lack the white spots. And, of course, many people are familiar with Red Admirals, black butterflies with bands of orange and white.
There are also Commas and Question Marks, darkly-colored butterflies that have jagged wings and small marks on the underside of their wings that resemble either a comma or a question mark. And, finally, of course, we have Monarch butterflies and their mimic, the Viceroy. Viceroys look very much like Monarchs, except that have an additional stripe running across their hind wings. Since predators avoid Monarch butterflies because they are toxic (thanks to the milkweed they eat as caterpillars), the Viceroy’s mimicry protects it, as well, despite the fact that it is perfectly safe to eat.
What’s nice about observing butterflies is that it’s so easy to do. They can be found almost anywhere and you don’t need any special equipment to see them. In many ways, butterfly-watching can be just as rewarding as bird-watching. In addition to being beautiful and fascinating, many butterflies also perform important ecological jobs such as pollinating flowers, crops, and other plants. They are also an important source of food for birds and other animals.
So, this summer, be sure to get out and try to observe some of our beautiful, graceful butterflies. You won’t be disappointed. If you’d like to attract and help out our butterflies and other pollinators, the best thing you can do is plant the host plants and flowers that they need. There are some excellent on-line resources for determining what to plant, or you can contact the Winnebago County Conservation Board at 641-565-3390 for more information.