Protection for Iowa butterfly may be too little, too late

CEDAR RAPIDS - A tiny butterfly once widespread in Iowa is a candidate for protection under the Endangered Species Act, a move that some experts say may be too late.

The Poweshiek skipper, which makes its home in native prairie remnants in Iowa and a few nearby states, was one of just three animal or plant species added to the list this year.

According to the U.S. Fish and Wildlife Service, sharp population declines have been documented in most of the butterfly's range.

“Of particular concern is its apparent disappearance from the majority of sites in the heart of its range in Iowa, Minnesota, and South Dakota,” the agency noted in announcing the list, adding that the Poweshiek skipper's high priority is “due to the imminence and magnitude of threats.”

The agency offers multiple tools to protect candidate species and their habitats, but the listing may have little impact, said Dennis Schlicht, co-author of “The Butterflies of Iowa.”

“They waited too long,” said Schlicht, 63, of Center Point, who sounded the alarm about the skipper years ago. “They're gone now.”

Schlicht, a retired Washington High School teacher in Cedar Rapids, said about 115 butterfly species inhabit Iowa.

Skippers, or skipperlings, are a type of butterfly sometimes mistaken for moths. At least 1,600 moth species - usually night-flyers with feathery antennae - inhabit Iowa. Butterflies generally fly during the day and have straight antennae.

The Poweshiek skipper, a small brown and orange butterfly with distinctive white veins on its wings, is one of several that have been disappearing in the past 10 years, Schlicht said.

He cited the Arogos, Ottoe and Dakota skippers and Prairie Ringlet and Purplish Copper butterflies among those nearly gone or extirpated - no longer inhabiting the state.

No one is certain why they have disappeared.

Climate change, with more frequent rains, pesticides and even one type of prairie management could all have an impact, Schlicht said.

He cited prairie burns as a management technique that may be harming insect populations. The controlled burns rejuvenate native plants by killing off invasive species, but may also kill insects, he said.

Frank Olsen, 65, of Cedar Rapids, said he doubted that prairie burns have been the primary cause of the demise, but added another possibility to the list.

The Asian lady beetle, relatively new to Iowa, made its appearance in the state at about the same time the Poweshiek skipper began its decline. He speculated that the beetle could be eating the skipper's tiny eggs.

Poweshiek skippers eat native grasses such as big and little bluestem as caterpillars and overwinter in Iowa in the larval stage. Adults, which live just one to two weeks in the summer, drink nectar from other prairie plants, including purple coneflower.

Olsen, a retired software installer and self-taught insect expert, was hired to survey the Poweshiek skipper's population in 2007.

He searched 26 locations where an Iowa State University student had documented as many as 150 skippers per site in 1993 and 1994.

“To my horror, I only found this skipperling at one site,” Olsen said. “The population had just plummeted.”

The Hoffman Prairie State Preserve in north-central Iowa had just two of the skippers.

Olsen said the Poweshiek skipper is emblematic of problems experienced by other Iowa pollinators.

He worked with a team that conducted an Iowa Department of Natural Resources survey for the Purplish Copper and Common Ringlet butterflies.

“None of us could find one of them,” he said. “It's kind of sad. We're essentially documenting the extirpation - the demise of these in Iowa.”

Harlan Ratcliff, 55, of Granger, who has studied the skipper for nearly a decade, said populations declined as Iowa's prairies began disappearing, but were stable in protected preserves.

“Scientists don't really know why they've disappeared from places where they were thought to be stable,” he said. “They managed to hold their own until just recently.”

Ratcliff said naming the skipper for protection may draw attention to it in states such as Wisconsin and Michigan, where some populations still exist.

He noted that a Grinnell College professor discovered the skipper and wrote the scientific description in 1870, naming it after Meskwaki Chief Poweshiek.

“It's really the only true species of butterfly discovered in Iowa,” he said. “It's kind of a shame to lose it from Iowa.”