Arctics – Oeneis butterflies on Notes from Nature

In 2015 the Triplehorn Insect Collection at The Ohio State University received a beautiful donation of more than 50,000 butterfly specimens. This gift came from a local teacher and butterfly enthusiast, David Parshall. It dramatically increased the depth and the breadth of our holdings of Lepidoptera – the moths and butterflies – including representatives of all the butterfly and skipper species found in the state of Ohio. The collection also includes many specimens of butterflies and skippers from Alaska and the Canadian Arctic regions.

A real highlight of the collection are specimens of the genus Oeneis. One of the common names of this group of butterflies is, appropriately enough, “Arctics.” They are found along rocky, mountainous terrain in alpine and sub-alpine habitats. The upper surface of the wings of these butterflies ranges from dull orange to delicate shades of brown and gray. The underside of the wings is beautifully mottled to appear like the rocky terrain and tree bark upon which the butterflies rest. Arctics are strong, fast fliers that are difficult to collect. As just one measure of the value of these donated specimens, they were part of the discovery and description of a species new to science, the Tanana Arctic, Oeneis tanana in 2016. This was the first new butterfly described from Alaska in 28 years.

Oeneis butterflies are adapted to living in the harsh Arctic conditions. They overwinter as caterpillars, and in those cold temperatures, it can take two years to grow from egg to adult. In the North the climate has a strong impact on survival, and so the distribution and flight periods of these butterflies are excellent indicators of environmental change.

Let’s not shy away from the elephant in the room: climate change. According to NASA the extent of sea ice on the Arctic Ocean is declining at a rate of 13.2% per decade. Researchers at the University of Colorado and the University of Wisconsin have concluded that average summer temperatures are now higher than they have been in more than 40,000 years. What will be the impacts of this warming trend? How has this trend already affected plants and animals of the Far North?

The Parshall butterfly collection can help provide some of the answers to these questions. There is evidence that butterflies living in the Arctic are already showing differences in size from the past. By documenting the distribution and flight times of these butterflies in past years, we can then compare the data with modern observations and better assess the impacts of climate change, human population growth, land use changes, etc. It can be difficult to tease apart the importance of each of these influences, but a comparison of similar changes in the distributions of other plants and animals can help to highlight possible common causes.

The first step, though, is the most important: where and when were specimens of these butterflies seen and collected over the past many years. By making the images and specimen data quickly and freely available online we hope to contribute to the investigation of the effects of global climate change on these butterflies. As part of the LepNet Project we at the Triplehorn Insect Collection have already digitized our entire holdings of skipper butterflies and made it fully available online. But there’s a lot of other butterflies still to go and we welcome all the help we can get from the vast community of citizen scientists interested in insect biodiversity.

One of the exciting things about science is that in trying to get an answer to one question, we always come across new discoveries which lead to even more questions. What amazing new knowledge will we gain from accessing all those specimen data? Where will that understanding lead us next? No one knows… yet. Come and embark on this adventure with us!

Find out more about our Arctic Oeneis databasing effort, see the people behind the images, and check out our data transcription tutorial on our project page.

— Norman F. Johnson & Luciana Musetti