Species Profile

Pale Yellow Dune Moth

Scientific Name: Copablepharon grandis
Taxonomy Group: Arthropods
Range: Alberta, Saskatchewan, Manitoba
Last COSEWIC Assessment: November 2007
Last COSEWIC Designation: Special Concern
SARA Status: Schedule 1, Special Concern

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Quick Links: | Description | Habitat | Biology | Threats | Protection | National Recovery Program | Documents

Image of Pale Yellow Dune Moth


The Pale Yellow Dune Moth is a medium-sized moth. In both sexes the forewings are pale yellow and the hindwings are white. The forewing, which varies in length from 16 to 20 mm, may have one or more small dark dots. The hindwing is uniform white in colour, but it may also have dark shading on the margin. There is some geographical variation. Specimens from the Great Basin, in the United States, tend to be smaller than those from the Great Plains, including Canada. The eggs are greenish white with a shallowly wrinkled upper surface and a smooth underside. The caterpillars (larvae), which can be up to 38 mm long, are light brown with white median and lateral lines. The cocoons (pupae, from which the adults will emerge) are about 19 mm long. The cocoon is protected by a layer of agglomerated sand granules.


Distribution and Population

The Pale Yellow Dune Moth is widely distributed in western North America. It has been found from southern California in the southwest to central Texas in the southeast and as far north as Lloydminster, Alberta. In Canada, the species has been captured in 10 localities in Alberta, Saskatchewan and Manitoba. Three of these localities were recently discovered, in 2004-2005. Some additional populations are likely to occur in the Canadian prairies.   There are no data on population sizes and long-term trends for the Pale Yellow Dune Moth. Other than 18 moths captured in light traps, it was not observed in the field in 2004-2005. Since the species requires semi-stable dunes, which are declining, the moth may also be in decline.



This moth forms isolated populations in sparsely vegetated sandy habitats, a regionally rare habitat in the southern Canadian prairies. The species is most often found in semi-stable dunes with sparse grass and forb cover. This association with loose, sandy soils suggests that the moth needs open sand in which to lay its eggs or for the development of the caterpillars. Based on the variability of plant species recorded within the immediate vicinity of sites in which the species is found, the Pale Yellow Dune Moth is not likely to be restricted to a single host plant for feeding or reproduction.



Little is known about the biology of this moth, which is difficult to observe in the field. However, it is known that the Pale Yellow Dune Moth has only one short flight season per year; in Canada, this season is approximately eight weeks long, from early July to late August. Eggs are fully formed in newly emerged females; mating and egg laying have not been observed. Eggs are believed to be deposited in the sand. The caterpillars emerge approximately three weeks later. The caterpillars likely feed on the above-ground parts of host plants during the night and spend the day buried in the sand; they may also feed on below-ground roots and shoots. The caterpillars likely overwinter in the ground, although conditions are unknown. In the spring, the caterpillars may feed before they pupate; the pupa stage is followed by the emergence of the adults. The Pale Yellow Dune Moth does not appear to be limited to a single host plant for nectar for the adults, for reproduction, or for food for the caterpillars.



The progressive stabilization of sand dunes caused by natural colonization is the main threat to populations of the Pale Yellow Dune Moth in Canada.   Grazing is considered a possible threat to this species. Grazing may maintain sparsely vegetated sandy habitats; however, the trampling associated with grazing may cause soil compaction and may crush eggs, caterpillars and cocoons. Grazing can also destroy the vegetation that the caterpillars feed on.   Intensive recreation in some sand dunes is also considered a possible threat to the Pale Yellow Dune Moth. Like grazing, recreation can result in loss of vegetation, disturbance to sand substrates, and destruction of eggs, caterpillars or cocoons. Recreation may also maintain or create open sand habitats.    Development activities, such as road building and petroleum infrastructure construction, that result in loss of natural habitats or mortality of moths are considered a possible threat to this species.   Finally, Canadian populations may be at risk of population collapse because of their small size and isolation. Because of these factors, these populations may be at increased risk of extinction.



Federal Protection

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

Provincial and Territorial Protection

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



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.

9 record(s) found.

COSEWIC Status Reports

COSEWIC Assessments

Response Statements

  • Response Statement - Pale Yellow Dune Moth (2008)

    Although the area of occupancy is small and there is some evidence of decline in its extent of occurrence and area of occupancy, the species persists in widely separated dune systems, the declines are not well documented, and the status of threats is unclear.  It requires semi-stable sand dunes which are declining.

Management Plans


COSEWIC Annual Reports

  • COSEWIC Annual Report - 2007 - 2008 (2008)

    2008 Annual Report to the The Minister of the Environment and the Canadian Endangered Species Conservation Council (CESCC) from the Committee on the Status of Endangered Wildlife in Canada.

Consultation Documents

  • Consultation on Amending the List of Species under the Species at Risk Act: Terrestrial Species (2009)

    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 20, 2009 for species undergoing normal consultations and by March 19, 2010 for species undergoing extended consultations.

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