Watching Washington Butterflies with Bob Pyle: Number Nineteen

The first time I ever beheld a Mourning Cloak, it was flapping across a field, past my face, then soaring, up and over a great domed cottonwood, into the far beyond. I recognized it from a picture in my Book of Knowledge, an old black-and-gilt encyclopedia. I was on my first-ever butterfly hunt, catching Painted Ladies. I will never forget it.

There is something about this big, one-of-a-kind butterfly that few can forget, once they’ve had a good look. Its ragged but regular outline, impressive bulk, and startling colors-seemingly confected from dark chocolate, French vanilla, and blueberries-impress themselves on the mind and the mind’s eye such that you find you’re looking for Cloaks evermore.

I remember particular Mourning Cloaks: one tussling with a Monarch, a Weidemeyer’s Admiral, and a big darner dragonfly in turn, as it patrolled a section of Colorado canal. Another, nectaring from pussy willows in a German town square in spring, as I nectared on good Pilsner below. A bright one bucketing down a busy street in Guadalajara, heedless of the traffic. A totally tatty one in late August in the Colorado foothills, a possible year-old survivor of the previous winter’s hibernation. And, not far from there, behind an old log lodge along the Peak-to-Peak Highway, a cherry-fresh individual drying its wings against a white aspen trunk, before tanking up on the sugars of asters and gentians for the coming winter.

I suspect few lovers of Nymphalis antiopa know much about its lifeways. member of the genus Nymphalis, the “type” genus of the whole family of brush-foots (Nymphalidae), it is a tortoise- shell-one of four species in Washington along with the California, the Compton, and Milbert’s, though it resembles none of those except in shape. It is also closely related to the anglewings or commas in the genus Polygonia. As such, it is one of eight species of butterflies in the state that overwinter strictly as an adult butterfly, finding shelter in a nest cavity, an old cabin, or a cave, for example. This is why we find bright, fresh individuals in the fall, and faded, often ragged ones in spring, depending on the winter they’ve spent. These eight may be seen on any unseasonably warm day of winter. But when they come forth for good, usually March or April, they vigorously seek both foodstuffs and mates. Since little nectar is available in early spring, they seek not only the small stores of it in pussy willows, but also flowing sap from frostcracked branches or sapsucker holes. Later they visit many flowers, as well as carrion, scat, and mud for the males. The marvelous photograph of mass Mourning Cloaks above shows them visiting dung.

Fed and mated, the females seek broadleaves such as willow, elm, rose, poplar, or hackberry to lay their eggs upon. Unlike most butterflies, but similar to checkerspots, they oviposit en masse, ringing a stem with dozens of eggs at a sitting. The resultant larvae feed communally and make quite a spectacle themselves, these spiny black, scarlet-spotted caterpillars all in a flock, as they make a mess of a willow branch. Then, after the fifth molt, they amble off to pupate alone or loosely grouped. As a boy, I found their chrysalides, like thorny corpuscles, hanging from their silken pads upside-down under the eaves of our house-not far from my mother’s weeping willow they had riddled.

This beloved butterfly has carried many names. Linnaeus named it in Latin after Antiopa (an Amazon or a lover of Zeus, depending on your myth) in his 1758 Systemae Naturae. As for its American common name, one story links it with the “widows’ weeds” (black mourning dress) so common after the Civil War; and its brilliant flash of yellow and blue edge was supposed to recall the singular advantage gained (at a time of great competition for young men) from young widows who flashed a bit of bright petticoat before the end of their official grieving period. “White Petticoats” is, in fact, one old name for the butter- fly. Some other languages carry a similar sense to the usual common name in English: Trauermantel in German, Sorgmantel in Swedish, for example. In Great Britain, the insect is an uncommon visitor known as the Camberwell Beauty, for having first been observed in that village (now suburb) outside London. But my favorite vernacular name for the insect is an old one also favored by Vladimir Nabokov: the Grand Surprise. Moses Harris applied this moniker in his 1775 The English Lepidoptera: or, the Aurelian’s Pocket Companion. I reckon it refers to the shock one is liable to receive when first seeing the dull aspect of the butterfly, from its ashen underside, transform into a splendid being robed in maroon, lined with gold, flecked with indigo, when it spreads its wings.

If there remain mysteries about the Mourning Cloak (as doubtless there do), one concerns its distribution and abundance. Why is it a common, even abundant butterfly in the Cascades and other places east of the crest, but scarce on the west side, where there is plenty of willow? Why, likewise, does it abound in Finland while being protected in Austria? Why is it considered a non-migrant resident, when sometimes clearly undertaking mass movements? And why was the year 2013 “The Year of the Cloaks” all over Washington, even in the West? That year, Thea and I saw more Mourning Cloaks in Gray’s River than during the entire preceding thirty years.

No doubt many factors pertain. But it seems to me that certain traits of the butterfly and its genus stand out, which may help answer most of these mysteries. First, even though (or perhaps because) it spends the winter as an adult, it clearly seems to prefer cold, dry conditions to cool, moist situations. I suspect the underlying cause here is rot (see my column number 8, February 2012, “Mold Butterflies: The Rot Factor.”) It is challenging for many organisms to persist in conditions too warm for hibernation, but too damp to avoid molds. Second, all of the tortoiseshells are notorious for radical population fluctuation and population displacement. The Compton Tortoiseshell (N. vaualbum) goes missing for years, then pops up in numbers, just like the Large Tortoiseshell (N. polychloros) in Britain. The California Tortoiseshell (N. californica) is of course the most dramatic about it, with its enormous booms and busts. But the other species go up and down in numbers too, and when more numerous, they expand their ranges as far and for as long as they can. They also undergo a degree of altitudinal migration (especially N. milberti) , and Cloaks are known to move latitudinally as well, perhaps to remove a portion of the population to less hostile winter conditions. Put all this together and you get a tortoiseshell stew, with species being listed one year and booming the next. Then add global warming, and things can get even stranger. Warmer, drier summers and colder winters may add up to Cloaks expanding their range, just as the Yellow-legged Tortoiseshell (N. xanthomelas) is doing in Europe. Camberwell Beauties may become com- mon in Camberwell. Grand Surprises may surprise us more often in Seattle and Aberdeen, as they did in 2013. We shall wait and see.

Although Mourning Cloaks occur around the northern hemisphere and well into Latin America, they have been consid- ered a single species, with few subspecies. Some, citing differences in size, shape, and ground color, are questioning this. If evidence mounts, perhaps there will be taxonomic changes for a butterfly that has been stable in name (if not numbers) for hundreds of years. But by whatever name; and however we encounter a Cloak-pale and ragged in March or rich and resplendent in September-it is always a special pleasure to meet in the out-of-doors, as it clicks past your face and evades your net handily should you try to catch it. Never has one stuck with me more than that first one, disappearing over the great cottonwood; unless it was the one I describe at the end of an essay bearing the butterfly’s old name, in a book called The Thunder Tree:

“The prone cottonwood trunks lay about like femurs in a bone-yard, hardly rotting in the desiccating air…the scene seemed lifeless. And just then something dark blew out of the hollowed rot wad. It was a Grand Surprise! Had it planned on spending the winter there? Mahogany vanes spread in an instant’s hesitation, flashing sapphire spots and yellow bands before my eyes, then sailed away.  I watched it with my binoculars as far as I have ever followed a butterfly in flight, maybe a mile. Then it disappeared. Not below the horizon-I could see the curvature of the earth-but up above it. Into a point.”

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