Area men document Iowa's moths

They say they believe at least 2,500 species are in state

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MARION — Most of what’s known about moths in Iowa has been discovered by two metro-area citizen scientists.

Working together for more than 15 years, Frank Olsen of Cedar Rapids and Jim Durbin of Marion — neither of whom has formal degrees related to their endeavor — have collected and identified representatives of more than 1,800 Iowa-dwelling moth species.

“If I had known at the beginning how many moth species live in Iowa, I never would have started,” said Olsen, 66, whose interest in moths preceded Durbin’s by a few years.

Durbin, 66, said the standard wisdom in the mid-1990s was that there are about 10 times as many moth species as butterfly species in Iowa. Given that fewer than 120 butterfly species had been identified in the state, “We thought, ‘1,200 species and we’re done,’ ” Durbin said.

The self-taught lepidopterists blew by that milestone several years ago and now believe that Iowa is home to at least 2,500 moth species.

They have been identifying about 100 new species per year but expect the rate to decline as they get closer to their goal.

“The longer you look, the smaller they get,” said Durbin, referring to the fact that they have identified all the large, distinctive species and are now down to rarer, nondescript species, many of which are no longer than an eighth of an inch.

The outliers are hard to find and often even harder to identify. Magnification and considerable research are often required to pinpoint distinguishing features, they said.

Since almost all moths are nocturnal, collection efforts are almost always conducted at night, according to Olsen, who spent much of Wednesday evening collecting moths in Shimek State Forest in southeast Iowa.

Typically they hang a white sheet in the woods and activate a battery-powered light fixture that includes a fluorescent tube and an ultraviolet tube — in essence, a black light of the type once used to illuminate psychedelic posters.

Attracted by the light, moths land on the sheet, where Olsen and Durbin photograph and collect them.

“The light also attracts opossums, skunks, park rangers and deputy sheriffs, which makes for some pretty interesting evenings,” Durbin said.

In what Olsen describes as a “museum quality display,” Durbin has about 15,000 mounted and preserved specimens stored in 120 specialized drawers. Olsen has an additional 6,500. They have taken a combined 29,000 moth photos and posted 28,000 records in a moth database available at

Their collections include representatives of 57 of the 74 moth families known in the United States.

Olsen estimates they have invested at least half an hour in each of the 28,000 moth records they have compiled. That includes finding the moth, photographing it, mounting it, identifying it and posting data on their website. Spreading the

Their joint effort equates to seven 2,000-hour work years, all accomplished as volunteers in service to the establishment of a scientific record that will prove valuable to the investigators who come after them. They hope their labor of love will inspire others to pick up where they eventually leave off, they said.

While many people recognize the beauty of some of the better known moths, such as the luna, sphinx and cecropia, few are familiar with the intricate markings and exotic colors of many lesser known species.

“They fly at night, when they are seldom seen. Why are they so pretty?” Olsen wonders.

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