The Poweshiek Skipper Project

I started the Poweshiek Skipper Project in 2005 in cooperation with The Center for Prairie Studies of Grinnell College. The project got quite a bit of assistance from local volunteers. The project had the specific goal of re-introducing the butterfly to Poweshiek County and surrounding areas, and involving local people in that effort. To that goal we declared a day to be "Poweshiek Skipper Day" and attempted to start a local celebratory event. We also had volunteers conduct butterfly surveys in areas where the butterfly could be re-introduced (an in theory could still possibly be found). And we had local students compete in a poster contest to promote either Poweshiek Skipper Day or the conservation of the species. We received significant assistance from a variety of sources, including some dedicated amateur naturalists and Reiman Gardens.

Reality has forced an evaluation and redirection of the goals of the project. Specifically, the populations of the butterfly have taken a nosedive. The species was thought to be rare but apparently secure when the project was started. That assessment was based on surveys taken to establish the status of another butterfly, the Dakota skipper, that were conducted in the mid 1990s. Those surveys found good populations of the butterfly in almost 30 different locations in Iowa. Butterfly researchers were starting to notice the absence of the butterfly from prairie preserves where it was previously found in about 2004 and subsequent years, but formal surveys were not conducted until 2007. The researchers seem to agree that the butterflies were present in those sites as recently as 2000. Those surveys indicated that the butterfly was not found most former sites and was found in very small numbers in two (maybe three) sites. Total numbers seen in the state of Iowa were less than half a dozen individuals for two or three years. One of the sites where it has been seen recently is a right-of-way site in northwest Iowa that is in no way secure. Similar population crashes have apparently taken place in southern Minnesota as well.

From the start our evaluation of the literature about O. poweshiek showed that not very much is known about the life history of the species. That lack of knowledge becomes even more critical with an increased realization of the rarity of the species.

What caused the populations to fall? A number of butterfly researchers have indicated that prescribed burning of prairie remnants has a detrimental effect of O. poweshiek populations. Most of the prairies where this butterfly was found have been managed by fire. However, not all have, apparently. Plus, most of the prairie sites were also managed by fire prior to the 1990s. Pesticides could be an answer. Pesticides were used prior to the 1990s, and probably in amounts greater than are used now. Outbreaks of soybean aphids, coupled with aerial spraying of huge areas of ground with insecticides starting around 2003 would seem to coincide with the disappearance of the species. Invasive species, particularly a very prolific Asian lady bug beetle showed up at approximately the same time. The bottom line is that we just don't know.

Originally, the intent of most of the efforts was to involve people in the re-introduction of the species to Poweshiek County or areas within counties adjacent to Poweshiek county. The problem is that now that original goal may not even be possible, due to the rarity of the species in Iowa. Re-introducing the butterfly is at the very least tabled for now--if it can happen it will be many years down the road.

So we have to evaluate what our plans and goals are now.

We appreciate all of the help we have had with the project so far, particularly by butterfly survey volunteers and people who have helped coordinate events. However, while we value their help we don't want to have them working for a project with false hopes. Therefore we will not use them until we have a better focus on what we will have them do. We have some ideas but we need to evaluate them and formalize them before we do much more with them for now.

This is a work in progress and additional information will be posted on this web site as appropriate.

Harlan Ratcliff