Species Profile

Weidemeyer's Admiral

Scientific Name: Limenitis weidemeyerii
Taxonomy Group: Arthropods
Range: Alberta
Last COSEWIC Assessment: May 2012
Last COSEWIC Designation: Special Concern
SARA Status: Schedule 1, Special Concern

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

Image of Weidemeyer's Admiral

Weidemeyer's Admiral Photo 1
Weidemeyer's Admiral Photo 2



The Weidemeyer's Admiral is a relatively large butterfly with a wingspan of 55 to 72 mm. It is mostly black with bold white bands on both wing surfaces and with extensive greyish white markings on the underside of the hind wings. Near the white band are small, relatively inconspicuous, red markings. The species' caterpillars can be olive-green with a mostly tan thorax (the segment behind the head), or greyish mottled with grey and white patches. Further back, there is a whitish-tan saddle on the middle of the dorsal surface and a whitish band on each side. The head is red-brown with small tubercles on the top. The pupae are blackish-brown with tan on the head and thorax and some areas of whitish and tan, a black streak on the dorsal surface, and slight greenish mottling.


Distribution and Population

This admiral is widely distributed in the western interior of the United States. In Canada, the only known resident population occurs along about 80 km of the Milk River valley in southern Alberta. The Canadian population, estimated at a maximum of 1800 to 3200 individuals, is naturally fragmented (reflecting the distribution of its habitat), but is probably stable.



Admirals use the woody riparian (along river banks) vegetation along the Milk River and its tributaries. Within the species' range, this vegetation naturally occurs as patches in a wide expanse of arid native grassland, badlands and croplands. The butterflies are typically associated with deciduous treed and shrubby areas which provide the necessary habitat ingredients: larval host plants, moisture and nectar sources for adults, and elevated perches for mate-locating by males.



Little information has been published on the biology of the Weidemeyer's Admiral. In Alberta, adult admirals have only one flight period per year, mostly from mid-June to mid July. Males may be territorial. They engage in both patrolling and perching types of mate-locating behaviour. They tend to patrol early in the day and later settle into perching sites. Females are seen less frequently as they spend much of their time in shrubs. They lay greyish-green eggs, placed singly on the upper side of the leaf tips of host plants, such as saskatoon, aspen, willow and wild cherries. The caterpillars eat the leaves of these plants. They hibernate through the winter. The following summer, they pupate and emerge as adults which feed on tree sap, flower nectar and carrion and also obtain moisture from mud. The Weidemeyer's Admiral can hybridize with other admiral species/sub-species where their ranges meet, but tends not to hybridize in areas of range overlap. Even though the Canadian population is patchily distributed, the species is very mobile. Genetic exchange between populations in these patches and with those in the United States is probably quite extensive.



The species is at the northern edge of its range and is presumably limited by climate. It is restricted to suitable habitat which is naturally patchy and limited within the butterfly's restricted range. The human population is sparse in this remote are, and urbanization is not a factor. The areas occupied by the butterfly are unlikely to be cultivated, but high intensity livestock grazing could potentially be detrimental to the species.



Federal Protection

More information about SARA, including how it protects individual species, is available in the Species at Risk Act: A Guide.

In Canada the Weidemeyer's Admiral has a very restricted range, but portions of it are protected in a provincial park, an ecological reserve and a natural area.

Provincial and Territorial Protection

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


Recovery Progress and Activities

Summary of Progress to Date Conservation strategies for individual ranches have been developed and implemented on some private ranches which contain habitat of the Weidemeyer’s Admiral. Summary of Recovery Activities Meetings are being held to inform the public about species at risk, such as the Weidemeyer’s Admiral. Workshops are being held with land owners to discuss management practices that would be beneficial for this butterfly.


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.

6 record(s) found.

COSEWIC Status Reports

  • COSEWIC assessment and status report on the Weidemeyer's Admiral Limenitis weidemeyerii in Canada (2013)

    Weidemeyer's Admiral is a relatively large, boldly patterned black and white butterfly. It has more white on its hind wing underside and reduced orange markings than the closely related Lorquin’s and White Admirals. As with related species, the larvae resemble bird droppings. The species represents a southern biogeographical element at the northern limit of its range along the Milk River, and is an important model for the study of speciation and mimicry.

Response Statements

  • Response Statement - Weidemeyer's Admiral (2013)

    This large butterfly has a small Canadian population and is restricted to valleys and prairie coulees of southern Alberta. The threat of invasive Russian Olive and Saltcedar that outcompete the butterfly’s larval host plant is predicted to increase. 

Management Plans

COSEWIC Annual Reports

  • COSEWIC Annual Report - 2011-2012 (2012)

    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 (September 1, 2011 to September 30, 2012) from November 21 to 25, 2011 and from April 29 to May 4, 2012. On February 3, 2012, an Emergency Assessment Subcommittee of COSEWIC also assessed the status of the Tri-colored Bat (Perimyotis subflavus), the Little Brown Myotis (Myotis lucifugus), and the Northern Myotis (Myotis septentrionalis). During the current reporting period COSEWIC assessed the status or reviewed the classification of 67 wildlife species. For species already found on Schedule 1 of SARA, the classification of 32 species was reviewed by COSEWIC and the status of the wildlife species was confirmed to be in the same category (extirpated - no longer found in the wild in Canada but occurring elsewhere, endangered, threatened or of special concern). The wildlife species assessment results for the 2011-2012 reporting period include the following: Extinct: 1 Extirpated: 4 Endangered: 29 Threatened: 10 Special Concern: 15 Data Deficient: 2 Not at Risk: 6 Total: 67 Of the 67 wildlife species examined, COSEWIC reviewed the classification of 49 species that had been previously assessed. The review of classification for 26 of those species resulted in a confirmation of the same status as the previous assessment (see Table 1a).

Consultation Documents

  • Consultation on Amending the List of Species under the Species at Risk Act: Terrestrial Species – December 2012 (2013)

    As part of its strategy for protecting wildlife species at risk, the Government of Canada proclaimed the Species at Risk Act (SARA) on June 5, 2003. Attached to the Act is Schedule 1, the list of the species that receive protection under SARA, also called the List of Wildlife Species at Risk. Please submit your comments by March 4, 2013, for terrestrial species undergoing normal consultations and by October 4, 2013, for terrestrial species undergoing extended consultations. Consultation paths.

Recovery Document Posting Plans

  • Environment and Climate Change Canada's Three-Year Recovery Document Posting Plan (2016)

    Environment and Climate Change Canada’s Three-Year Recovery Document Posting Plan identifies the species for which recovery documents will be posted each fiscal year starting in 2014-2015. Posting this three year plan on the Species at Risk Public Registry is intended to provide transparency to partners, stakeholders, and the public about Environment and Climate Change Canada’s plan to develop and post these proposed recovery strategies and management plans. However, both the number of documents and the particular species that are posted in a given year may change slightly due to a variety of circumstances. Last update March 31, 2017