It’s a lazy late summer afternoon. The flowers are busy with butterflies hurrying to gather nectar, mate, and lay their eggs before fall. As I watch, a striking butterfly with dark, yellow-edged wings flutters past. This butterfly, known as the Mourning Cloak, is different. Unlike the others, it will not die in the fall. Instead, it will live through the coldest months of winter to re-emerge in the spring, a feat that never fails to amaze me.
The Mourning Cloak (Nymphalis antiopa) is one of my favourite butterflies. It’s uniquely patterned wings make it one of the few butterflies that I can always identify confidently, even if I only catch a glimpse of it as it flutters by. The upper side of the Mourning Cloak’s wings is a rich, velvety maroon colour, trimmed with jewel-like blue spots and edged in yellow. The common name of “mourning cloak” may make this butterfly sound like it should be dark and drab, but perhaps one of its other common names (such as Camberwell Beauty, White Petticoat, Grand Surprise, Antiopa, or Yellow Edge) would better suit its rich and elegant beauty.
The Mourning Cloak lives in North America and Eurasia in open meadows, fields, forests, and riversides. The female Mourning Cloak lays her eggs on the leaves of willow, elm, poplar, birch, or hackberry. Like other butterflies, the young feed and grow as caterpillars before pupating and eventually emerging as adult butterflies. As adults, Mourning Cloaks are cleverly camouflaged. Their wings have jagged edges and the underside is a mottled brownish grey. With their wings closed, these butterflies can resemble a piece of bark or a dried leaf, but when the wings flash open, the bright yellow edge can startle and distract birds, giving the butterfly time to escape.
However, the main reason that I love Mourning Cloaks is their amazing ability to survive the long, cold months of winter. When cold temperatures come, these butterflies tuck themselves in under a piece of bark, a shutter, or any other nook or crevice, and their bodies produce a natural antifreeze which allows them to survive the cold. They come out of their hibernation in the first warm days of spring (in some areas, you might even see one on a warm winter’s day), making them one of the earliest butterflies to appear – although by this time they’re looking a bit tattered, their yellow edges faded to a dull white. After emerging in spring, they feed, mate, lay their eggs, and finally come to the end of their life span. It is possible, however, that some adult Mourning Cloaks may live for nearly a year, much longer than most butterflies, which may only live for a few weeks.
Butterflies are often perceived as delicate, fragile creatures, but as I shiver on a cold winter’s day while bundled up in a coat, sweater, hat, and gloves, I can only marvel at how a tiny insect – incapable of producing its own body heat as mammals do – can survive. “In all things of nature there is something of the marvelous,” wrote Aristotle, and the Mourning Cloak butterfly is an excellent example of how even the smallest life form can harbour astonishing abilities and qualities before which we humans can only stand in awe.
Here in southern British Columbia, Canada, we have already had our first frost and before too long the days of seeing butterflies on the wing will be over for this year. But as I wait for next year’s spring, I will think of the Mourning Cloaks.