Highlighted Story: Prairie Butterflies

Exploring Ex Situ Options for Prairie Butterflies

CBSG used the IUCN SSC Guidelines on the Use of Ex Situ Management for Species Conservation to guide a planning workshop for threatened prairie butterflies in the US Midwest and Canada.

Photos © Minnesota Zoo



  • Poweshiek skipperlings and Dakota skippers are native to mixed-grass and tallgrass prairie, moist meadow, and prairie fen ecosystems. 
  • Only about 1% of the original tallgrass native prairie in the US remains, making it one of the most endangered ecosystems in the world.
  • Prairie butterflies present ex situ challenges, such as host plant specificity and winter hibernation requirements. Alternatives to breeding programs such as headstarting and research using surrogate species can provide conservation benefits.

The Situation
Poweshiek skipperlings (Oarisma poweshiek) and Dakota skippers (Hesperia dakotae) are small butterfly species native to parts of the US and Canada. Large-scale conversion of their prairie habitat to agriculture and other anthropogenic threats have resulted in dramatic population decline and fragmentation. In addition to the implementation of habitat and population management efforts in the field, experts managing both species are exploring options for ex situ management. The US Fish and Wildlife Service (USFWS) and the Minnesota Zoo invited CBSG to facilitate a participatory workshop process using the IUCN SSC Guidelines on the Use of Ex Situ Management for Species Conservation to evaluate the feasibility of incorporating an ex situ management element into broader conservation activities.

The Process
During the workshop, butterfly experts examined various threats impacting the demographic rates and population status of these species in the wild, and identified potential ex situ conservation roles to address those threats. After a thorough analysis of the cost, risks, and feasibility of each management option, the participants recommended specific ex situ components to adopt as part of a larger conservation strategy for each species and discussed an action plan for program implementation. Actions for population management in the field were also incorporated into the plan.


The Results
A mixed-programs strategy was determined as the best way forward for both species, incorporating a series of ex situ roles over time as appropriate. With full support from USFWS, the Poweshiek skipperling working group is moving forward with all of the workshop recommendations for ex situ programs for Poweshiek skipperling and Dakota skippers. They are now working through the IUCN’s reintroduction and translocation guidelines to develop a formal plan to augment Michigan populations of Poweshiek skipperling with larvae head-started at the Minnesota Zoo starting summer of 2016. The zoo is also working to expand its Dakota skipper collection to provide the numbers needed to begin reintroductions in 2017, as recommended.