The great arctic (Oeneis nevadensis) butterfly will be back this year and should soon be spotted at the Metolius Preserve! Though maybe not as well known and easily identifiable as a monarch, these native butterflies are special in their own right. The beautiful orange-brown species is biennial, meaning it takes two years to complete metamorphosis. The great arctic hibernates as a young caterpillar their first winter, and then as mature caterpillars through their second winter. They are primarily seen in highest abundance in even numbered years (it’s 2024!) due to their long life cycle. Their flight typically begins in late June and extends through August.

How to identify the great arctic:
Let’s begin with the wings. The upper side of the wings are orange-brown to pale orange in color with two eyespots on the forewing, and usually one small black spot on the lower corner of the hindwing. The eyespots on butterflies can confuse predators sometimes causing them to strike the wing thinking it is the butterfly's head. Even with a small bite taken out of its wing, a butterfly can still fly. The hindwing and the forewing of the great arctic have black outer borders. The underside of the wings can be described as cloudy brown or gray brown, often helping the butterfly blend in on logs, rocks, and bark. The great arctic is also the largest of the western arctics, measuring in at 2-2.5 inches.

Where to look for them:
The great arctic butterfly is found almost exclusively in Oregon, Washington, and British Columbia in the Cascade Mountains. The open, coniferous forest of the Metolius Preserve provides excellent habitat for the butterfly, and the rocky hills and meadow edges of the Cascades provide places for males who perch all day seeking females.

Host plants:
Unlike the monarch butterfly that has a well-understood and required relationship with native milkweed to reproduce, the host plant for great arctic caterpillars is unknown. Eggs are laid on dry grasses, and the pupation stage of their metamorphosis happens at roots of grasses or under rocks.

Butterfly watching:
Butterflies are very delicate, beautiful creatures. Here are a few things to keep in mind as you head out to look for butterflies:

• Use close-range binoculars to watch them from a distance. Like bird watching, you can learn a lot about butterflies by viewing them through binoculars.
• Be patient. Butterflies move around, but if you stand still they will eventually land and you can find them in your binoculars.
• Try a net. Butterfly nets can be helpful for close viewing of butterflies. To help keep the butterflies safe, however, we highly recommend that you learn how to use a net before you try. Learn how.
• Wear bright colors. Butterflies are attracted to bright colors and you may be lucky enough to have one land on you!

Learn more:

• Join us for a guided butterfly walk!
• Tips for an excellent butterfly expedition.
• Discover other butterflies you can find in Central Oregon.

Sources:

• The Butterflies of Cascadia: A Field Guide to all the Species of Washington, Oregon, and Surrounding Territories. By: Robert Pyle, Idie Ulsh, and David Nunnallee.
• Life Histories of Cascadia Butterflies. By: David James and David Nunnallee.
• Butterflies and Moths of North America