Where cicadas are welcomed

out of hibernation

Over two to three weeks, cicada nymphs, which have the longest developmental cycle of any insect, emerge from the ground after 17 years of sucking xylem from tree roots to molt into adults, finds Patricia Leigh Brown.

Lawrence F Gall, an entomologist at the Peabody Museum of Natural History at Yale, bushwhacked his way through the muddy thickets leading to the River Road colony here, the epicentre of what is believed to be the world’s only preserve dedicated to Magicicada septendecim, the 17-year periodical cicada. “They’re super-de-duper dense,” he observed, examining some of the roughly one million cicada nymphs that call this place home — about 1,500 to 2,000 of them per square yard. Just in time for graduation, the East Coast from Connecticut to northern Georgia is alive with newly emerging adults —only they make far more of a racket than the ones in caps and gowns. It is 17-year-cicada season, and grown men like Gall —who as a boy would get up in the middle of the night at summer camp to collect moths under a bathroom light — may be seen crawling on their hands and knees to confront insects with vermilion eyes, black thoraxes and golden gossamer wings, the sharp, entomological equivalent of a zoot suit.

Over two to three weeks, periodical cicada nymphs, which have the longest developmental cycle of any insect, emerge from the ground after 17 years of sucking xylem from tree roots to molt into adults. They latch on to stable vertical surfaces —trees, telephone poles, rural mailboxes —to shed their exoskeletons, a tricky gymnastic manoeuvre. Five days later, their wings elongated, their bodies pumped and tan, the cicadas are ready to make music together — the males congregating to sing in chorus, usually on high, sunlit branches; the females flicking their wings in response. Thus begins a complex and deafening courtship, each cicada a tiny bit of drama.

Although Connecticut lies at the northern fringes of this year’s emergence, known collectively as Brood II, the state is hallowed ground for cicada history and scholarship. The Peabody Museum, where the exhibition “Return of the 17-Year Cicadas!” is on display until September 3, contains specimens of Magicicada septendecim from 1843, the oldest at any museum. The preserve (not open to the public) is on 90 acres owned by the South Central Connecticut Regional Water Authority, just north of Sleeping Giant State Park, a popular hiking spot. It was the brainchild of Charles Lee Remington, a longtime professor at Yale who was the Peabody’s first curator of entomology. Though a pioneering lepidopterist, Remington did much to popularise the periodical cicada, once organising a tasting at the Peabody and creating his own recipes. His popular class, “The Biology of Terrestrial Arthropods,” inspired generations of scientists, who would go on to study not only cicadas but butterfly genetics, cave crickets and the ant ecology of the Thimble Islands in Long Island Sound, to name a few.

Remington, who died in 2007, appreciated the thoughtful gesture, like a box of mounted cockroach specimens from Ghana sent by a former student, Leonard E. Munstermann, the Peabody’s current head curator of entomology. “He had a particular flair for extinct and endangered creatures at the edge of their range,” said Gall, another of his protégés. “Cicadas have an extraordinary and intriguing lifestyle, even for insects.”

Remington established the Magicicada Preserve a year before the 1996 emergence, to protect what he viewed as “an endangered phenomenon.” He visited his forest frequently, writing elaborate field notes by hand that sometimes transcended cicadas. On April 26, 1996, for instance, he helped an 85-year-old man who had fallen on the trail. “Left leg crumpled & he cut face falling,” he wrote. “Remembered 2 Magicicada hatches ('Noise Extremely Loud’).”

Today, scientists from the Cicada Molecular Systematics Lab at the University of Connecticut are using GIS-GPS technology to map Magicicada populations with an accuracy unimaginable when the preserve was founded — some 10,000 individual locations so far (including the hot-off-the-press discovery of a Brood II pocket in northeastern Georgia, posted on the project’s website, magicicada.org). One of those scientists is John R Cooley, who studied with Remington as an undergraduate. He has become the Alan Lomax of cicadas, recording and analysing their songs. He and other University of Connecticut researchers are comparing GIS-GPS to crowdsourcing data from citizen scientists, an effort called Cicada Watch, to map emergences at the margins.

In creating the preserve in Hamden, Remington wanted to raise awareness of cicadas and their special biology in an untouched habitat, said the University of Connecticut lab’s founder, Chris Simon, a professor of ecology and evolutionary biology. “He could see that their territory was being taken away,” she said. Although it may seem counterintuitive, periodical cicada populations have been shrinking and even disappearing. The reasons, scientists suggest, have to do with climate change and land development. Among the endangered cicada populations is Brood VII, in upstate New York, now largely restricted to the Onondaga Nation south of Syracuse.

On Long Island, a Wal-Mart in Port Jefferson Station was built on top of a large cicada population, Simon said. Chris T Maier, an entomologist with the Connecticut Agricultural Experiment Station, said that from 1945 to 1979, the state lost roughly 5 per cent of its cicada population, much of it as a result of Interstate System highway development. Among the mysteries as yet unsolved, Simon said, is the “internal clock that lets them count the passing of years and the genetic control mechanism for when they arrive early or late.”

A major goal of the mapping projects is to develop a baseline for future researchers so that population loss can be tracked. Simon laments the telephone calls she receives from freaked-out suburbanites wanting to get rid of their cicadas. “It’s crazy,” she said. “They’re only inconvenienced for two weeks every 17 years.”