How a Famed Novelist Became a Godfather to a Tiny Endangered Butterfly
Habitat protection holds new promise for survival of Karner blue butterfly
When Vladimir Nabokov identified a tiny American butterfly as a distinct subspecies in 1944, he had no reason to think the insect would someday become endangered. One of the twentieth century's great novelists, Nabokov was also a skilled amateur entomologist who made significant contributions to the science of lepidopterology--the study of butterflies. His work classifying the Karner blue, as the subspecies was called, was part of his overall research on a widespread group of butterflies, the blues, to which it belongs.
By the time of Nabokov's death in 1977, scientists had already recognized the little butterfly as an insect on the skids. By 1992, when the Karner blue landed on the U.S. Endangered Species List, some experts thought the creature’ s days were numbered.
The Karner blue’ s problems stem from its adaptation to life in sandy pine-oak savanna, where natural fires spur the growth of wild lupine, the only plant that Karner caterpillars eat. As that unique habitat has disappeared, so have its insects. Formerly found across the northeastern United States, the northern Midwest and even into Ontario, the butterfly today hangs on only in isolated populations in seven states: Indiana, Michigan, Minnesota, New Hampshire, New York, Ohio and Wisconsin.
Lately, though, the Karner blue´s dim future has turned a bit brighter, at least in the western part of its range. In September 1999, the U.S. Fish and Wildlife Service (FWS), along with the Wisconsin Department of Natural Resources and 25 private landowners, launched a Habitat Conservation Plan that aims to protect the butterfly on 262,000 acres in the sand counties of central and northwest Wisconsin.
"We’re in the heart of the Karner blue butterfly range," says Cathy Carnes, a FWS endangered species coordinator in Green Bay, Wisconsin. "We have more populations of the butterflies and larger areas that can be managed for the butterfly" compared to the Northeast’s small populations and bits of sand-barren habitat. That’s why Carnes believes the insect’ s Midwest populations can bounce back.
Having a literary giant for a godfather undoubtedly has helped promote the butterfly’ s cause. Although it had been known to American biologists since the mid-nineteenth century, when it was first recorded near the village of Karner in eastern New York State, the tiny blue (its wings spread no wider than a postage stamp) was plucked from obscurity after catching the eye of the butterfly-mad novelist.
Born in 1899, Nabokov was a Russian aristocrat who fled from Nazi Europe to the United States in 1940. Author of 17 novels, he is best known for the controversial Lolita, published in 1958. However, he had yet another professional identity. Nabokov was a self-taught lepidopterist who did valuable studies on New World butterflies. "Frankly, I never thought of letters as a career," Nabokov once claimed. "On the other hand, I have often dreamt of a long and exciting career as an obscure curator of lepidoptera in a great museum."
In fact, Nabokov did make significant contributions to the study of insects he had adored since childhood. "Although it took scientists 50 years to catch up with the significance of his early work," says Kurt Johnson, lepidopterist and coauthor of the book Nabokov’ s Blues, "the emphasis on biodiversity studies in the 1990s revealed that Nabokov´s taxonomies had laid a solid foundation for understanding the entire blue butterfly fauna of the New World."
It was Nabokov-as-researcher who, while working for little or no money at Harvard University’s Museum of Comparative Zoology in the 1940s, reclassified the Karner blue, naming it Lycaeides melissa samuelis. His study of the butterfly’ s reproductive anatomy had convinced him that the Karner blue of the eastern United States was, in fact, a subspecies of a type of butterfly found as far west as the Rocky Mountains, if not a species in its own right.
In 1957, Nabokov-as-novelist sketched a portrait of Karner blues in his book Pnin: "A score of small butterflies, all of one kind, were settled on a damp patch of sand, their wings erect and closed, showing their pale undersides with dark dots and tiny orange-rimmed peacock spots along the hindwing margins." Momentarily disturbed, the butterflies, "revealing the celestial hue of their upper surface ... fluttered around like blue snowflakes before settling again."
During the 1940s and 1950s, Nabokov kept track of Karner blues in the extensive pine barrens around Albany, New York. He reported that both lupines and butterflies were "still doing as fine under those old gnarled pines along the railroad as they did ninety years ago." But in time, the butterfly´s fortunes declined. Roads, new homes, shopping malls and other projects gradually consumed the rolling sand plain that once constituted the 40,000-acre Albany Pine Bush. In the process, one of the continent’ s largest populations of Karner blues was brought to near collapse and remains in a precarious state today. (Authorities estimate the population may number as few as 500 adults.)
However, even before anyone had paved a single pine barren in any part of the insect´s range, the Karner blue was already a bug on the run. A specialized organism that biologists refer to as a "fugitive species," the butterfly was both hounded and aided by fire.
Historically, when wildfires sparked by lightning swept across parts of the pine barrens, Karner blue populations in the path of a blaze were instantly destroyed. But the same fires burned off undergrowth; on the freshly cleared land lupine, on which Karner females lay their eggs, flourished. The natural butterfly gardens lured Karner blues from nearby areas and a fresh colony of the insects took root.
These days, because development has obliterated many pine barrens or carved the habitat into isolated fragments, there usually is not a Karner blue population near enough to repopulate a burned area. Still, recent research suggests that the insects can migrate as far as a mile to new habitat under certain conditions. "They don't like to move through heavily shaded areas that don't have any nectar plants to kind of lead them on," says Carnes.
For that reason, Wisconsin woodland owners participating in the Karner blue Habitat Conservation Plan have offered to cut treeless "dispersal corridors" through forests they manage. With nectar plants, including lupine, growing in the corridors, butterflies should find their way to good habitat. As part of the plan, the Wisconsin Department of Transportation will avoid mowing areas with lupine until the end of summer, when Karner blues are no longer active.
In return for butterfly-friendly land management (which benefits other rare savanna species), government agencies and private landowners in Wisconsin may be able to conduct normal operations on their land without running afoul of the Endangered Species Act. Even if their activities destroy some butterflies or habitat, the Karner blue as a subspecies may be better off.
With this project and others, the diminutive blue butterfly that fluttered famously through the mind and works of one of the last century’ s greatest novelists may continue to play a role in the book that is life on Earth.
Washington, D.C., journalist Michael Lipske wrote about sagebrush in the October/November issue.