Great arctic (Oeneis nevadensis gigas)

Category: Butterflies and moths
State status: Candidate
Vulnerability to climate change (More details)

Low-
Moderate

If you see this species, please share your observation using the WDFW wildlife reporting form. Providing detailed information such as a photo and exact coordinates will improve the confidence and value of this observation to WDFW species conservation and management.

The population of the great arctic gigas subspecies in Washington is critical and the trend is unknown. If this butterfly persists in Washington, population sizes are likely small. A Pacific Northwest endemic, this butterfly has been found on a single site within the United States, in northwestern Washington; it also occurs in southwestern British Columbia and may occur on other sites with similar habitat. It is a "Species of Greatest Conservation Need" due to its restricted range, distribution, and habitat, and many threats to its grassland-forest edge habitat.

Description and Range

Physical description

The great arctic, a member of the Satyr (Satyrinae) butterfly subfamily, is a large tawny brown butterfly with a bark-like patterned ventral hindwing, such that when perched they are quite camouflaged. Wingspan is up to 2.5 inches.

Ecology and life history

Great arctic belongs to a group of butterflies, the arctics and alpines, that inhabit far northern and alpine climes. The great arctic inhabits forest openings, meadow edges, and rocky slopes and outcrops from sea level to mid-elevations. Aside from dependence on specific but unknown grasses and forest edge ecotone, little is known of their habitat requirements.

The life history of great artic is not well known. One unusual aspect of their life history is a life cycle, from egg to adult that spans two years.

Adults are present in June and July, and females lay eggs on unknown species of grasses where larvae develop over two years; the timing and location of larval and pupal stages are unknown. This two-year life cycle is synchronized amongst individuals and results in adults mostly occurring in even-numbered years.

Males exhibit territorial flight behaviors of perching and patrolling, and are known to congregate on ridges and hilltops, a behavior called “hilltopping”. This butterfly’s habits of jerky flights through open forest and perching on trees where they are concealed makes them difficult to detect.

Geographic range

The great arctic gigas subspecies occurs in British Columbia, primarily on Vancouver Island, with a few sites in the mainland Coast Range, and a single site known from Washington, on Orcas Island (San Juan County) in the northwestern portion of the state. Recent efforts to relocate great arctic on Orcas Island have been inconclusive; WDFW surveyors had fleeting observations of unidentified but similar looking butterflies, and they located additional potential habitat for future survey. If this butterfly persists in Washington, population sizes are likely small.

For a map of range-wide distribution and conservation status of the great Arctic butterfly species, check out NatureServe Explorer.

Climate vulnerability

Sensitivity to climate change

Low-
Moderate

There is no information regarding the sensitivity of this species to climate change, and very little known regarding its life history. As an occupant of forest openings and meadow edges, it may benefit from more frequent fire which contributes to the creation of these habitat characteristics. However, larvae are thought to develop on grasses, and could be killed by fire. Small population sizes and limited distribution in Washington make it vulnerable to extirpation.

Confidence: Low

Exposure to climate change

Low-
Moderate

  • Altered fire regimes
Confidence: Low

Conservation

This species is identified as a Species of Greatest Conservation Need (SGCN) under the State Wildlife Action Plan (SWAP). SGCN-classified species include both those with and without legal protection status under the Federal or State Endangered Species programs, as well as game species with low populations. The WDFW SWAP is part of a nationwide effort by all 50 states and five U.S. territories to develop conservation action plans for fish, wildlife and their natural habitats—identifying opportunities for species' recovery before they are imperiled and more limited.
This species is identified as a Priority Species under WDFW's Priority Habitat and Species Program. Priority species require protective measures for their survival due to their population status, sensitivity to habitat alteration, and/or recreational, commercial, or tribal importance. The PHS program is the agency's main means of sharing fish and wildlife information with local governments, landowners, and others who use it to protect priority habitats for land use planning.

Conservation Threats and Actions Needed

  • Resource information collection needs 
    • Threat: Current status and distribution in Washington is unknown. 
    • Action Needed: Survey historic locale and other potential sites. 
  • Invasive and other problematic species
    • Threat: Forest encroachment due to long-term fire suppression has reduced amount and quality of habitat. Host plant is a grass, and this butterfly utilizes open forest and forest edge.
    • Action Needed: Survey historic locale and other potential sites. 

See the Climate vulnerability section above for more information about the threat posed by climate change to this species.

Resources

References

Dornfeld, E. J. 1980. Butterflies of Oregon. Timber Press, Forest Grove, Oregon. 276 pp.

Guppy, C. and J. Shepard. 2001. Butterflies of British Columbia: including Western Alberta, Southern Yukon, The Alaska Panhandle, Washington, Northern Oregon, Northern Idaho, and Northwestern Montana. University of British Columbia Press, Vancouver, B.C.

Pyle, R. 1989. Washington butterfly conservation status plan. WDFW. Olympia. 216 pp.

Pyle, R.M. and LaBar, C.C. 2018. Butterflies of the Pacific Northwest. Timber Press. 461 pp.

WDFW publications

Other resources