Commentary: Butterflies offer world more than beauty
Posted by collegegreenou on September 29, 2009
By Joe Brehm
Investigations Editor and Commentator
Sitting atop an oak-hickory ridge at Sells Park on a warm, sunny July afternoon, I had a close encounter with a Banded Hairstreak (Satyrium calanus). As I sat on a cool, shaded rock I noticed some movement along the adjacent trail. Two tiny butterflies battled wildly for a small, sunny forest glade, or opening. A typical butterfly battle doesn’t last more than a few seconds, but these tiny gladiators spun around each other like a cyclone for a minute or more at a time. They would cease fire for a few minutes and then resume their wild spinning. Immediately impressed by their intensity and endurance, I crept closer to get a better look at who these tiny titans were. The winner of the territorial dispute kept returning to the same sunny perch, which enabled me to sneak close enough to see the well-developed white bands on the underwing. I had to get pretty darn close, as Hairstreaks are roughly the size of a nickel. These white bands give the Banded Hairstreak its name and set it apart from other Hairstreaks, many of which look extremely similar.
As it perched, this Banded Hairstreak rubbed its shiny, glimmering wings together and displayed them from all angles.
The little butterfly eventually took off for a moment and alighted on my shoulder on its return. Without warning, I was face to face with the creature. As we stared at one another, I couldn’t help but be humbled by this experience. Banded Hairstreaks have been battling over forest glades and the nectar they provide for tens of millions of years, and I was able to witness a brief and tiny slice of their natural history.
Butterflies such as these are not only beautiful and awe-inspiring, but fill a crucial ecological niche, help give birth to a new branch of scientific study and require careful land management to ensure their conservation.
What’s the big deal about butterflies? Aside from their stunning beauty and diversity, butterflies are part of a crucial group of organisms known as pollinators. Without pollinators, humans would be without roughly one third of the foods we eat.
Pollinators such as bees, wasps, butterflies and moths transfer pollen between flowers of the same species, a necessary step in the production of a fruit. Blossoms on apple trees, for example, must be pollinated before they are able to produce apples. The melon plants in my garden are no exception, and I have regularly seen a few small species of butterflies flitting from one bright yellow blossom to another. Thanks to Zabulon Skippers, Least Skippers and Silver Spotted Skippers, I will soon be enjoying melons out of the garden.
Plants and Lepidoptera: Like Peas and Carrots
In addition to providing an essential ecological service, butterflies are simply impressive creatures. Their evolution is closely tied to that of flowering plants, which begin to show up in the fossil record about 135 million years ago. In fact, scientists studying the interactions between butterflies and flowering plants gave birth to a new scientific field in the 1960’s called “coevolution”. This discipline seeks to understand how the interactions of different types of organisms affect each other’s evolution over time, rather than studying an organism’s changes in isolation.
Butterflies’ coevolution with flowering plants is revealed in their anatomy. Their mouthparts have evolved into a long, coiled tube called a proboscis. Butterflies uncoil their proboscis and probe deep into flowers to suck up precious nectar. Nectar sustains adult butterflies as they flit, flap, soar and glide in search of mates and places to lay their eggs. It also provides the fuel necessary for Hairstreak battles like the one I observed. Nectar from plants such as Common Milkweed (Asclepias), Butterfly Milkweed (Asclepias tuberose), Ironweed (Vernonia gigantean) and Spreading Dogbane (Apocynum androsaemiflorum) sustains some species in mind-boggling migrations. Butterflies such as the Monarch, Painted Lady (Vanessa cardui), and Red Admiral (Vanessa atalanta) travel great distances each year. The Monarch takes the prize of greatest distance traveled, making an amazing multi-generational, 2,000 mile round trip journey from Mexico to Canada each year that scientists are only beginning to understand.
In Ohio there are currently about 144 species of butterflies, according to the Ohio Lepidopterists Society. They come in a variety of shapes, colors, sizes and when they appear throughout the spring, summer, and fall. Common species in southeast Ohio range from the tiny Eastern-tailed Blue to the enormous Tiger Swallowtail, which glides on huge, black-striped yellow wings. In between in size are species such as the Red-spotted Purple, a black butterfly with deep, iridescent blue on its hind wings and reddish spots on the underwing, and the Eastern Comma, with ragged-edged wings and a white mark on the underwing that resembles the punctuation mark for which it is named. Each species of butterfly also has a unique flight pattern, which can help in their identification. Small skippers, such as the Silver Spotted Skipper, dart rapidly from flower to flower, their conspicuous silvery spot flashing with each quick wing beat. With a much different flight pattern, huge butterflies such as the Monarch and Tiger Swallowtail can glide for ten seconds or more on large, colorful wings.
Because of the complexity of a butterfly’s life cycle, its dependence on certain plants and habitats and seasonal migrations, it is a challenge to manage land for butterfly conservation. This challenge is being met in places in Ohio, however. The Karner Blue (Lycaedes melissa samuelis), a butterfly previously extirpated from Ohio almost thirty years ago, was successfully reintroduced to the Oak Openings region of Ohio near Toledo in the summer of 2008. The Karner Blue is dependent on oak savannah habitat, a rare habitat in Ohio, and the Wild Lupine (Lupinus perennis), prairie grasses, and nectar sources that are found in this type of habitat. A partnership between the Ohio Department of Natural Resources, The Nature Conservancy, Toledo Metroparks, the Toledo Zoo, the Ohio Lepidopterists Society (OLS), and the U.S. Fish and Wildlife Service restored this small, beautiful blue butterfly’s habitat and released 250 Karner Blues in the summer of 2008. The restoration effort has been largely successful, thus far.
The OLS furthers butterfly conservation through monitoring efforts. They have set up transects all over the state to monitor butterfly populations, which I participate in. The monitoring consists of walking a designated trail and recording the species and abundance of butterflies that you have the pleasure of encountering. OLS compiles the data from all of these transects to essentially understand how butterflies are doing in Ohio. Check out their website for more information and keep an eye out for the winged wonders around southeast Ohio.
The way we manage land in southeast Ohio and across the state will determine the future of the Banded Hairstreak and other species of butterflies. It is necessary to provide butterflies with a suitable habitat — nectar sources, food plants and natural corridors — to ensure that these pollinator populations will remain healthy. The main threat to butterflies is sprawling urban or suburban development, which not only destroys habitat, but also impedes butterfly movements from one patch of habitat to another. Species such as the Karner Blue also depend on disturbances such as fire to maintain their savannah habitat.
A Lifelong Study
Insect families such as the Lepidopterans, which include butterflies and moths, continue to remind me of how little I know about the world. Spending time studying these creatures is a perpetual exploration of beauty and the delicate balance of the natural world. I distinctly remember the first time I was awed by butterflies.
Sitting on a sandy, forested dune overlooking Lake Michigan several years ago, a monarch landed on the ground by my side. At the time, I was not so curious about how it came to be there or where it was going — it was simply beautiful. The monarch’s striking orange, black and white wings flapped open and shut as it perched next to me on the sand and fallen leaves. There were no other people or animals around — just me, the monarch, the gentle lapping of waves on the shore and the cool breeze off the lake. I get the same feeling of wonder and humility each time I come face to face with one of these amazing creatures.