On a very hot and sunny August afternoon in the South Okanagan a butterfly species, which was previously thought to be extirpated (i.e. no longer found) from areas north of Osoyoos, was found on a property owned by The Nature Trust of British Columbia near Vaseux Lake.
The Mormon Metalmark butterfly has not been seen in the South Okanagan valley north of Osoyoos since 1929. This individual butterfly was found by biologists Terry McIntosh and Allison Haney on a boulder cooling off near a creek. The multi-coloured Mormon metalmark butterfly is named for the white metallic-looking markings on its wings.
The Southern Mountain population of the Mormon Metalmark butterfly is federally listed as Endangered under the Species at Risk Act. The Southern Mountain population is primarily found on steep sandy or gravelly rocky slopes with Snow Buckwheat plants, which was characteristic of this site.
Snow Buckwheat is the host plant for Mormon Metalmark and is used for larval development. Typically these butterflies do not disperse more than 4 kilometres and this site is more than 20 kilometres north of Osoyoos. Future studies will need to be done to confirm whether this discovery was a wandering individual or recolonization of this area.
The primary threat to this species is habitat loss and degradation. The presence of this endangered species on a Nature Trust conservation property demonstrates the importance of continuing to protect the lower grassland and shrub-steppe plant communities, along with their associated rocky slopes, in the South Okanagan valley.