Biologists track, map cicada distribution across nation

Periodical cicadas – the noisy creatures that pop up once every 13 or 17 years – were out again this year. And two researchers in the Department of Ecology and Evolutionary Biology, John Cooley and Chris Simon, set out to track and map their distribution across the nation, with support from the National Geographic Society.

Cooley, a research associate at UConn, organized a large team of scientists to conduct the work, including researchers from Simon’s lab and others from Pennsylvania, Ohio, Maryland, Massachusetts, and Japan. The team also relied on volunteer cicada enthusiasts to help cover ground and track the creatures.

Simon, a professor of ecology and evolutionary biology, monitored the effort from her UConn lab, providing feedback to the team in the field and answering inquiries about the emergence of the periodical cicadas, a species known as Magicicada.

This year’s emergence was of one particular brood of cicadas, known as Brood XIV, which is on a 17-year cycle. The next emergence, three years from now, will be of Brood XIX.

Cooley adapted new mapping and GPS technologies that facilitate rapid assessment by ‘cicada SWAT teams’ and instant plotting onto maps.

He also set up a website: http://magicicada.org/ that shows current cicada mapping and also includes information about species, behavior, broods, and frequently asked questions for anyone who is curious.

Some of the maps showing where periodical cicadas emerge date from as far back as the 19th century and are, not surprisingly, outdated, says Simon. They also overestimate periodical cicada range limits.

The UConn lead team spent much of May and June on the road, living out of their cars, locating and mapping the distribution of the cicadas. They found dense populations from the mountains of Northern Georgia to the oak forests of Cape Cod.

The researchers say the work has ramifications beyond updating the maps.

“The questions involved are not trivial,” they wrote on the web site. “Periodical cicada responses to deglaciation may provide insights into the possibility that they are useful for monitoring forest and ecosystem health, while the biogeography of broods and species may provide critical insights into the general nature of species, speciation processes, and gene flow between species. Modern transportation, highly accurate base maps, GPS technology, and a better understanding of periodical cicada biology provide unprecedented opportunities for accurately mapping Magicicada populations.”