By Alyssa Nyberg, Restoration Ecologist at The Nature Conservancy’s Kankakee Sands
Ready for a grand surprise? Summer is not the only time to see butterflies at Kankakee Sands. March can be, too!
Wait, what—March? Believe it or not, if you head out for a walk on a sunny day this chilly month March in an open woodlands or savanna – such as Conrad Station Savanna on the north end of Kankakee Sands – or a park, or even backyard where trees are present, there’s a good chance you may see a mourning cloak butterfly (Nymphalis antiopa).
Unlikely as it may seem, they really are out there! But they’re a little hard to see. When the large, 3-inch jagged-edged wings of the mourning cloak are folded in a closed and resting position, the dull-grey color of the wings blends perfectly with the tree bark or fallen leaves where it may be resting.
It’s this dull grey color for which it was named, resembling the cape or coat worn by someone who is in mourning. But when those wings open, the creamy yellow edges of the wings, decorated with a long row of royal blue oval edges will grab your attention and shroud you in a cloak of delight. Does me every time!
And then off it will go fluttering away in an instant. These fast-flying butterflies are quick and wary, which serves them well. As you might imagine, a juicy-bodied butterfly would be a fine meal for a hungry bird, reptile, amphibian, larger dragonfly or praying mantis. Given the 30,000 acres of natural areas owned by The Nature Conservancy and DNR in Newton County, there’s no shortage of any of those predators!
The mourning cloak butterfly is found throughout North America and even in the temperate regions of Eurasia. In Great Britain it is an irregular migrant, and therefore has been affectionately called the grand surprise. It certainly is an exciting, grand and fun surprise for us in Indiana when we see it in March after what always feels like a long, cold winter!
Mourning cloaks overwinter as adults in hollow logs, tree cavities and under bark. The overwintered adults have tattered wings, but seeing a butterfly in March is often so exciting and wonderful that we overlook it’s not-so-vibrant appearance.
Overwintered adult mourning cloaks will mate in the spring and lay eggs on the twigs of host plants that the caterpillars will eat when they hatch: willows, elm, poplar, hackberry and cottonwood. Unlike monarch caterpillars, which eat by themselves, mourning cloak caterpillars feed together, communally munch, munch, munching away. Because the eggs and caterpillars are a protein rich food for a wide array of hungry insects (including beetles, ants, and wasps), many of the eggs and caterpillars do not reach the butterfly stage.
In May, the mourning cloak caterpillar – velvety black, speckled white and with spiny bristles – forms a chrysalis and pupates. Adult mourning cloak butterflies emerge in June and July with fresh vibrant wings and will feed on the sap of trees and fallen fruits, but rarely will they nectar on flowers. At this time of year, the other Indiana butterflies—swallowtails, monarchs and red admirals, to name a few—paint the landscape with their bold oranges, yellows and blues. As they fly about and nectar on eye-catching flowers, it’s all too easy to overlook the mourning cloak. That’s why March is a grand month to see the grand surprise.
But if you don’t see one this month, fear not! The chances of seeing one this year are great. Mourning cloaks have one of the longest lifespans of our Indiana butterflies – 11 to 12 months! And in years (such as this one) when we have had warm spells during the winter, they have been documented in every month of the year, though they are most commonly observed from March through November.
We will be hosting two upcoming group opportunities in April and May to see mourning cloaks at Conrad Station Savanna. Please join us!
- Jeanette Jaskula, President of Friends of the Sands, will be leading a mothing excursion at Conrad Station Savanna to inventory the moths that come to a sticky sweet bait she makes out of fermented bananas and beer and spreads on the trunks of trees. That concoction doesn’t sound to tasty to us, but the mourning cloaks can’t resist!
- We will be hosting several volunteer workdays to remove non-native, invasive garlic mustard plants, which are aggressive and shade out our spring wildflowers. It’s quite satisfying to pluck unwanted garlic mustard plants from the ground, and seeing a mourning cloak butterfly is icing on a volunteer workday cake!
To stay in the know about upcoming mothing opportunities, visit our events calendar at nature.org/indianavolunteer this spring, visit the great outdoors and treat yourself to a grand surprise!
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The Nature Conservancy’s Kankakee Sands is an 8,400-acre prairie and savanna habitat in Northwest Indiana, open every day of the year for public enjoyment. For more information about Kankakee Sands, visit www.nature.org/KankakeeSands or call the office at 219-285-2184.
Friends of the Sands 