COSEWIC Assessment and Status Report on the Columbia Dune Moth Copablepharon absidum in Canada DATA DEFICIENT 2017 COSEWIC status reports are working documents used in assigning the status of wildlife species suspected of being at risk. This report may be cited as follows: COSEWIC. 2017. COSEWIC assessment and status report on the Columbia Dune Moth Copablepharon absidum in Canada. Committee on the Status of Endangered Wildlife in Canada. Ottawa. x + 44 pp. (http://www.registrelep-sararegistry.gc.ca/default.asp?lang=en&n=24F7211B-1). Production note: COSEWIC acknowledges Nicholas A. Page for writing the provisional status report on Columbia Dune Moth (Copablepharon absidum) prepared under contract with Environment Canada and completed in 2006. The contractor’s involvement with the writing of the status report ended with the acceptance of this provisional report. At that time, the Arthropods Specialist Subcommittee decided additional field verification was required prior to the species assessment and the status report was put on hold. In 2016 additional fieldwork was completed and the report updated by Jennifer Heron. For additional copies contact: COSEWIC Secretariat c/o Canadian Wildlife Service Environment and Climate Change Canada Ottawa, ON K1A 0H3 Tel.: 819-938-4125 Fax: 819-938-3984 E-mail: [email protected] http://www.cosewic.gc.ca Également disponible en français sous le titre Ếvaluation et Rapport de situation du COSEPAC sur la Noctuelle jaune du bassin Columbia (Copablepharon absidum) au Canada. Cover illustration/photo: Columbia Dune Moth — Photo by Jocelyn Gill. Specimen housed at the Canadian National Collection of Insects, Arachnids and Nematodes, Ottawa, ON. Her Majesty the Queen in Right of Canada, 2017. Catalogue No. CW69-14/750-2017E-PDF ISBN 978-0-660-08704-7 COSEWIC Assessment Summary Assessment Summary – April 2017 Common name Columbia Dune Moth Scientific name Copablepharon absidum Status Data Deficient Reason for designation This moth is known from open and sparsely vegetated sand dune habitats at three localities (Kaslo, Lillooet, and Osoyoos) within the southern interior of British Columbia. While open sand habitats are rare in the province, and declining in quality, suitable habitat still remains. However, surveys to verify occurrences since the last record in 1953 have been too infrequent and are insufficient to draw any conclusions about extent of occurrence, population size, threats, or trends. Occurrence British Columbia Status history Species considered in April 2017 and placed in the Data Deficient category. iii COSEWIC Executive Summary Columbia Dune Moth Copablepharon absidum Wildlife Species Description and Significance The Columbia Dune Moth, Copablepharon absidum, is a medium-sized moth (forewing length 16–19 mm) in the family Noctuidae. The forewings are yellow or yellow- orange, often with olive-grey shading, and two slightly paler streaks along its wings. The Columbia Dune Moth is closely associated with sparsely vegetated sandy habitats in the driest and warmest regions of Canada. It is one of several focal species representing the sensitivity and uniqueness of this habitat type in Canada. Distribution The global range of the Columbia Dune Moth is from southern British Columbia (BC), south to the United States through the arid interior of Washington to southern Oregon, and east into Idaho. In Canada, the moth is known from three localities, all in BC and separated by large distances of unsuitable habitat: Lillooet (collected once in 1916), Kaslo (collected once in 1923), and Osoyoos (numerous specimens collected in 1953). Habitat The Columbia Dune Moth is primarily associated with open and arid sparsely vegetated, sandy habitats including low elevation Antelope-brush and Sagebrush steppe, sandy grasslands, and dunes. In BC, these habitats are often adjacent to rivers or lakes that experience periodic sand accretion and deposition thereby maintaining open sandy habitat with few trees. Biology Little is known about the biology of the Columbia Dune Moth. There have been no observations of mating, egg laying, larval development, or pupation in Canada. However, sampling records elsewhere in the species’ range indicate it is bivoltine and adults fly from late April to early June and again from late July to early October. Dispersal abilities have not been assessed, but there is no information that indicates it migrates. iv Columbia Dune Moth does not rely on a specific host plant for its life cycle. Collections in Washington State have recorded larvae in sand beneath an unidentified sand-verbena plant, grass, and a trailing legume. Captive-bred larvae complete development and emerge as adults after a one-month pupal stage. Early instar larvae also overwinter, similar to other moths in the Copablepharon genus. Population Sizes and Trends There is no quantitative information on population sizes and trends for the Columbia Dune Moth in Canada or elsewhere in the species’ global range. Loss of sandy habitat at Osoyoos and Lillooet combined with more widespread changes to arid habitats throughout its range suggests that subpopulations, if present, have also potentially declined. The Kaslo specimen was collected prior to the installation of the Corra Linn Dam on Kootenay Lake, which flooded natural sandy habitats at the lakeshore. Repeated sampling has failed to detect the Columbia Dune Moth at or near historical population sites. The closest known population in the United States is near Brewster, Washington, approximately 106 km south of the historical locality at Osoyoos. The possibility of recolonization over this distance is unlikely, although further sampling in the intervening area is required. Surveys to verify occurrences since the last record in 1953 have been too infrequent and are insufficient to draw any conclusions about extent of occurrence, population size, threats, or trends. Threats and Limiting Factors Development activities that result in direct loss of sandy habitat are a threat to the Columbia Dune Moth. This includes the conversion of open natural sandy habitats to agriculture, predominantly vineyards. Conversion or decline in habitat quality may also occur through other activities such as urban housing and commercial development, off-road vehicle use, livestock ranching, and natural system modifications. The Columbia Dune Moth in Canada may be at risk from demographic collapse; subpopulations are spatially isolated and may have increased risk of extirpation. Demographic collapse is considered a limiting factor that exacerbates the effects of other threats. Protection, Status and Ranks Columbia Dune Moth is not protected in any jurisdiction in Canada. The BC Conservation Data Centre has assigned the species the conservation status rank of SH (historical). v TECHNICAL SUMMARY Copablepharon absidum Columbia Dune Moth Noctuelle jaune du bassin Columbia Range of occurrence in Canada: British Columbia Demographic Information Generation time 4-8 months assuming Canadian population to be bivoltine. Is there an [observed, inferred, or projected] continuing Not applicable. decline in number of mature individuals? No records of this species in Canada for 63 years (last record 1953). Estimated percent of continuing decline in total number Not applicable. of mature individuals within [5 years or 2 generations] [Observed, estimated, inferred, or suspected] percent Not applicable. [reduction or increase] in total number of mature individuals over the last [10 years, or 3 generations]. [Projected or suspected] percent [reduction or increase] Not applicable. in total number of mature individuals over the next [10 years, or 3 generations]. [Observed, estimated, inferred, or suspected] percent Not applicable. [reduction or increase] in total number of mature individuals over any [10 years, or 3 generations] period, No records of this species in Canada for 63 over a time period including both the past and the future. years (last record 1953). Are the causes of the decline a. clearly reversible and a. No. b. understood and b. No. c. ceased? c. No. Are there extreme fluctuations in number of mature No individuals? The number of specimens caught in light traps elsewhere within the species’ range is not substantial or considered to indicate extreme population fluctuation. Extent and Occupancy Information Estimated extent of occurrence (EOO) 6,220 km2 based on its capture in three historical localities: Lillooet (1916); Kaslo (1926); and Osoyoos (1953). Index of area of occupancy (IAO) 12 km² (Always report 2x2 grid value). Assuming historical localities may still be extant. vi Is the population “severely fragmented” i.e., is >50% of its a. Unknown. total area of occupancy in habitat patches that are (a) b. Unknown. smaller than would be required to support a viable population, and (b) separated from other habitat patches by a distance larger than the species can be expected to disperse? Number of “locations”∗ (use plausible range to reflect 3 locations. uncertainty if appropriate) Is there an [observed, inferred, or projected] decline in Unknown. extent of occurrence? Is there an [observed, inferred, or projected] decline in Unknown. index of area of occupancy? Is there an [observed, inferred, or projected] decline in Unknown. number of subpopulations? Is there an [observed, inferred, or projected] decline in Unknown. number of “locations”*? Is there an [observed, inferred, or projected] decline in Yes. Inferred. Based on decline in habitat area, [area, extent and/or quality]