ALWAYS IN SEASON: Butterfly encounter offers up a Zhuangi moment
Butterfly encounter offers
n Mourning cloak a widespread species in N.D.
While I was sitting in the garden chair, a butterfly landed on my knee. It was a mourning cloak, a big, boldly marked and very beautiful butterfly.
A bit of Chinese wisdom came to mind. “One time I dreamt I was a butterfly” the sage Zhuang Zhou wrote 23 centuries ago, “fluttering hither and thither, a veritable butterfly, enjoying itself to the full of its bent. ... Suddenly I awoke and came to myself. Now I do not know whether it was then I who dreamt I was a butterfly, or whether I am now a butterfly dreaming that I am a man.”
I won’t dwell on Zhuang’s insight. He’s right. We can’t be sure.
Instead, I’m savoring the brief encounter. To have a butterfly taking a rest on your knee? It’s just not an everyday occurrence.
A mourning cloak specimen 2½ inches across its wings would be considered small. Individuals sometimes reach more than 3 inches from wingtip to wingtip.
The wings are a dark reddish-brown, and they are edged with pale cream yellow. Beyond the wing’s edge, toward the body and past the yellow edging, there is a line of blue dots that runs along both the front and rear wings. At the leading margin of the front wings, there are two comma-shaped spots of yellow. In all, this is a striking combination. It is also unique among butterflies.
The dark color apparently gave northern Europeans the idea of mourning. In German, the butterfly is called “Trauermantel,” and mourning cloak is a direct translation.
The American name is evidence that immigrants recognized the butterfly from their experiences in Europe and readily called it by names they already knew.
The mourning cloak is a circumpolar species, found across Europe and Asia. In North America, it is common just about everywhere — but the butterflies find Florida too warm for their liking. The species is unusual there.
In North Dakota, “The species flies statewide,” Ron Royer says in “Butterflies of North Dakota.” There are records for most parts of Manitoba, including some from the far north. In Montana, the mourning cloak is known and loved so well that it has been named the state insect.
The mourning cloak bears the cold remarkably well and overwinters here sometimes under loose bark on trees, sometimes in abandoned buildings. Nor does the mourning cloak wait for heat to emerge in spring. They’re sometimes seen as early as April in the Red River Valley, often before the snow is completely melted. This is exceptionally early for any insect, and so the mourning cloak can be conspicuous, even though its plumage is sometimes worn.
The butterfly’s coloration may help it survive chilly spring days. Perhaps their dark wings help them to absorb heat and warm their bodies.
Mourning cloak butterflies often feed on sap. I find them frequently at the sap wells that yellow-bellied sapsuckers drill into the elm and cottonwood trees at our place west of Gilby, N.D. Royer confirms this, saying of the mourning cloak, “It is extremely fond of sap runs.”
Mourning cloak numbers fluctuate during the year, with peaks both spring and fall. During midsummer, mourning cloaks are less numerous.
Probably, the adults that survived the winter have laid eggs and produced a new generation, and the adults that emerge winter over the next year.
That makes a rather long lifespan for an insect, from 10 months at least and sometimes up to a year. Nevertheless, it is a good evolutionary strategy. Overwintering saves the energy that would be used in migration. Perhaps more important, it gives the species a head start on its most important business, reproducing itself.
Mourning cloak larvae are wonders in themselves. The caterpillars are black and speckled with white spots. A line of red spots runs down the middle of the back.
Like other butterflies, the caterpillars form pupae. These are gray-brown and suspended head down. This stage of the mourning cloak’s life is brief. Adults emerge in about 10 days.
Mourning cloaks are strong fliers. The one on my knee moved away after about 10 minutes. It headed west, toward Montana, where it enjoys that special, official status.
Jacobs is a retired publisher of the Herald. Reach him at firstname.lastname@example.org.