Species Profile

Poweshiek Skipperling

Scientific Name: Oarisma poweshiek
Taxonomy Group: Arthropods
Range: Manitoba
Last COSEWIC Assessment: November 2014
Last COSEWIC Designation: Endangered
SARA Status: Schedule 1, Threatened

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Quick Links: | Photo | Description | Distribution and Population | Habitat | Biology | Threats | Protection | Other Protection or Status | Recovery Initiatives | National Recovery Program | Documents

Image of Poweshiek Skipperling

Poweshiek Skipperling Photo 1



The Poweshiek Skipperling is a small brown butterfly with a wingspan of 24 to 30 mm. Males and females have similar coloration. The upper side of the wings is dark brown with orange along the wing margin and base. The underside of the front wing is a distinctive dark brown, with orange areas along the front margin contrasted with white veins and white over-scaling on the hindwing. Eggs are pale yellowish-green, 0.7 mm in length, and have a slightly elliptical shape. Caterpillars are light green with a dark green stripe on the top, bordered by white on either side. They have six white-to-cream-coloured stripes, and an average length of 24 mm.


Distribution and Population

The Poweshiek Skipperling has a very limited and highly fragmented distribution in North America. It occurs in the United States in only one area in Michigan and Iowa, and a number of isolated sites in western Minnesota. In Canada, it is found only in southeastern Manitoba, in a 2300-ha area near Tolstoi, Stuartburn, and Gardenton. Populations of Poweshiek Skipperling are estimated to be in the range of 5 000 to 10 000 adults; however, no detailed or long-term population trends are available.



The Poweshiek Skipperling is found only in the native tall-grass prairie of southeastern Manitoba, consisting of both wet and dry habitats, each with a distinctive plant community used by the butterfly at different life stages. The Poweshiek Skipperling caterpillar feeds on Slender Spike Rush, a host plant found in the wetter areas. The adult feeds on the nectar of a variety of flowering plants, including Black-eyed Susan, that grow in the drier sections.



The adult Poweshiek Skipperling is active for only about three to four weeks, usually from late June to mid- or late July, with peak numbers of adults usually during the second week of July. The female lays eggs on host plants such as Slender Spike Rush and other sedges, which hatch in 9 to 10 days. Caterpillars feed on the leaves of the host plant, and rest on the underside of the grass stems. The Poweshiek Skipperling goes through seven larval stages (instars), and overwinters in the leaf litter of the host plant. It emerges in spring to feed and form a chrysalis. The adult emerges in late June or July; there is only one generation per year.



The Poweshiek Skipperling is presumed to be in decline as a result of the conversion of tall-grass prairie habitat into agriculture. Over 99.5% of the native prairie habitat in Manitoba has been converted to agricultural row crops or hay fields, habitats unsuitable for this skipper. Overgrazing and haying (depending on the time of year) eliminate both adult nectar sources and larval food plants. Other threats include controlled burning (depending on timing and intensity), succession, exotic species, and habitat fragmentation.



Federal Protection

The Poweshiek Skipperling is protected under the federal Species at Risk Act (SARA). More information about SARA, including how it protects individual species, is available in the Species at Risk Act: A Guide.

The habitat of most populations is protected in the Tall-grass Prairie Preserve established through the federal Critical Wildlife Habitat Program. A few additional sites outside the preserve are on privately owned land.

Provincial and Territorial Protection

To know if this species is protected by provincial or territorial laws, consult the provinces' and territories' websites.


Other Protection or Status

The World Conservation Union (IUCN) classifies the Poweshiek Skipperling as Vulnerable.


Recovery Initiatives

Status of Recovery Planning

Recovery Strategies :

Name Recovery Strategy for the Poweshiek Skipperling (Oarisma poweshiek) in Canada
Status Final posting on SAR registry


Recovery Progress and Activities

Summary of Recovery Activities The Nature Conservancy of Canada-Manitoba is restoring natural Poweshiek Skipperling habitat by controlled burns and selective mowing to remove invasive species. Ecologically sensitive land is being secured through purchase, donation, and conservation easements which will target areas with species at risk such as the Poweshiek Skipperling.


PLEASE NOTE: Not all COSEWIC reports are currently available on the SARA Public Registry. Most of the reports not yet available are status reports for species assessed by COSEWIC prior to May 2002. Other COSEWIC reports not yet available may include those species assessed as Extinct, Data Deficient or Not at Risk. In the meantime, they are available on request from the COSEWIC Secretariat.

11 record(s) found.

COSEWIC Status Reports

  • COSEWIC assessment and status report on the Poweshiek skipperling Oarisma poweshiek in Canada (2015)

    The Poweshiek skipperling is a member of the Family Hesperiidae, the skippers, and the Order Lepidoptera, the butterflies and moths. No subspecies are recognized for this species. Adults of the Poweshiek skipperling have a wing span of 24 to 30 mm. There is very little difference in coloration between the sexes. The upper side of the wings is very dark brown with orange over-scaling along the margin and basal area of the front wing. The underside is very distinctive. The underside of the front wing is dark brown with orange areas along the front margin. The veins on the anterior portion of the underside of the hind wing are white with white over-scaling between the veins. This light area sharply contrasts with the very dark brown inner margin of the underside of the hind wing. The pale yellowish-green eggs are slightly elliptical and about 0.7 mm in diameter. The caterpillars are light green with a dark green dorsal stripe bordered on each side with white. There are six pale (white to cream) lateral stripes. The mature caterpillar attains a length of about 24 mm.

COSEWIC Assessments

Response Statements

  • Response Statement - Poweshiek Skipperling (2004)

    This species occurs in Canada in a very small restricted area at 15 locations in a single metapopulation which is an isolated disjunct, with the closest population in the United Stated being about 100 km to the south. In Canada, the species is dependent on native tall-grass prairie, a habitat that has suffered enormous losses in the past, and its populations have likely undergone similar declines. Although remnant prairie habitat that supports the butterfly is unsuitable for agriculture and most of it is protected in a prairie reserve, past fire management to maintain prairie vegetation has been detrimental to the butterfly. Most of the occupied habitat is protected, but even with appropriate management, its range is so small that the butterfly is vulnerable to catastrophe.
  • Response Statement - Poweshiek Skipperling (2015)

    The Canadian population is isolated and disjunct from the populations in United States which are 1000 km to the south.  Widespread declines within the past decade on both sides of the border mean Canada holds a significant portion of the species global range. Within Canada this species is restricted to native tall-grass prairie, a habitat that has also undergone similar declines. Although most of the occupied habitat is protected, even with appropriate management, its range is so small that the butterfly is increasingly vulnerable to stochastic events.

Recovery Strategies

  • Recovery Strategy for the Poweshiek Skipperling (Oarisma poweshiek) in Canada (2012)

    The Poweshiek Skipperling was listed as Threatened under the Species at Risk Act in July 2005. The Minister of Environment is the competent minister for the recovery of the Poweshiek Skipperling and has prepared this strategy, as per section 37 of SARA. It has been prepared in cooperation with government of Manitoba.


  • Order Acknowledging Receipt of the Assessments Done Pursuant to Subsection 23(1) of the Act (2004)

    The Order acknowledges receipt by the Governor in Council of the assessments of the status of wildlife species done pursuant to subsection 23(1) of the Species at Risk Act (SARA) by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC). The purpose of SARA is to prevent wildlife species from being extirpated or becoming extinct, to provide for the recovery of wildlife species that are extirpated, endangered or threatened as a result of human activity and to manage species of special concern to prevent them from becoming endangered or threatened.
  • Order Amending Schedules 1 to 3 to the Species at Risk Act (2005)

    The Minister of the Environment is recommending, pursuant to section 27 of the Species at Risk Act (SARA), that 43 species be added to Schedule 1, the List of Wildlife Species at Risk. This recommendation is based on scientific assessments by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) and on consultations with governments, Aboriginal peoples, wildlife management boards, stakeholders and the Canadian public.

COSEWIC Annual Reports

  • COSEWIC Annual Report - 2004 (2004)

    2004 Annual Report to the Canadian Endangered Species Conservation Council (CESCC) from the Committee on the Status of Endangered Wildlife in Canada.
  • COSEWIC Annual Report - 2014-2015 (2015)

    Under Canada’s Species at Risk Act (SARA), the foremost function of COSEWIC is to "assess the status of each wildlife species considered by COSEWIC to be at risk and, as part of the assessment, identify existing and potential threats to the species". COSEWIC held two Wildlife Species Assessment Meetings in this reporting year (October, 2014 to September, 2015) from November 23 to November 28, 2014 and from April 27 to May 1, 2015. During the current reporting period, COSEWIC assessed the status or reviewed the classification of 56 wildlife species. The wildlife species assessment results for the 2014-2015 reporting period include the following: Extinct: 0 Extirpated: 1 Endangered: 21 Threatened: 11 Special Concern: 21 Data Deficient: 1 Not at Risk: 1 Total: 56 Of the 56 wildlife species examined, COSEWIC reviewed the classification of 40 that had been previously assessed. The review of classification for 24 of those wildlife species resulted in a confirmation of the same risk status as the previous assessment.

Consultation Documents

  • Consultation on Amending the List of Species under the Species at Risk Act : Terrestrial Species - January 2016 (2016)

    The Government of Canada is committed to preventing the disappearance of wildlife species at risk from our lands. As part of its strategy for realizing that commitment, on June 5, 2003, the Government of Canada proclaimed the Species at Risk Act (SARA). Attached to the Act is Schedule 1, the list of the species provided for under SARA, also called the List of Wildlife Species at Risk. Extirpated, Endangered and Threatened species on Schedule 1 benefit from the protection of prohibitions and recovery planning requirements under SARA. Special Concern species benefit from its management planning requirements. Schedule 1 has grown from the original 233 to 521 wildlife species at risk. Please submit your comments byMay 4, 2016, for terrestrial species undergoing normal consultationsand byOctober 4, 2016, for terrestrial species undergoing extended consultations.For a description of the consultation paths these species will undergo, please see:Species at Risk Public Registry website
  • Consultation on Amending the List of Species under the Species at Risk Act: November 2004 (2004)

    The Government of Canada proclaimed the Species at Risk Act (SARA) on June 5, 2003 as part of its strategy for the protection of wildlife species at risk. Attached to the act is Schedule 1, the list of the species that receive protection under SARA, hereinafter referred to as the 'SARA list'. Canadians are invited to comment on whether all or some of the species included in this document should be added to the SARA list.