Larval Host Plant Selection and Daily Behavior of Poweshiek Skipperling (Oarisma poweshiek) in Michigan

Abstract

Conservation efforts depend greatly on a working knowledge of the species of concern. Little is known about the basic biology of many endangered species regarding their life history information. This is true for the Poweshiek skipperling butterfly (Oarisma poweshiek), whose larval host plant is not yet known for Michigan populations. This is concerning as Michigan is where the least is known about the life history of the Poweshiek skipperling and where the greatest number of populations are currently. In this study we investigated the larval host plant by following the butterflies in the field to observe egg laying events. All of the observed events in this study we observed on mat muhley grass (Muhlenbergia richardsonis). This critical information will be helpful in the future conservation action taken to save the Poweshiek skipperling from extirpation from Michigan sites. We also conducted a daily activity budget survey for the Poweshiek skipperling. No individuals were observed before 0923 h and none were seen after 1830 h. The results from these surveys will be used to provide suggested alterations to the current population surveys that the Michigan Natural Features Inventory is conducting. These changes to survey technique could provide more efficient use of time for the surveyors and allow the organization to conduct more in depth surveys and more surveys in each given flight season.