This species' common name comes from the town of Compton in the Eastern Townships of Québec where it was studied by the English naturalist Phillip Henry Gosse. N. vaualbum is a member of the Nymphalinae subfamily (16 species in Canada, 13 found in Ontario) and one of four North American species in the Tortoiseshell group. All species in this group have cryptic, camouflaged coloration on their underside. The Canadian populations belong to subspecies j-album.|
Identification: The scientific name for this species, vaualbum, is from the Greek "vau" for "V", and "album" is from the Latin for white. This describes the small white V- shaped markings on the underside of the hindwings, which are otherwise marbled grey and brown. There is also a white patch found on the upper margins of the fore and hindwings on a rust brown background. Wingspan: 52-70 mm.
Life History: Eggs are laid in large groups. One brood per season. Hibernates as an adult. Larvae are pale green and speckled, with branched black spines. Young larvae feed communally. Adults are long-lived like most tortoiseshells. They overwinter in natural or artifical cavities and re-emerge the following April at which time they become sexually active. New generation individuals can be seen basking on logs in September and October.
Habitat and Range: Precambrian woodlands, adults can be seen alighting in clearings and cutlines of forested areas. In the Ottawa District it is rare to uncommon. In Ontario it is widespread and sometimes common as far north as James Bay. It is found throughout Canada south of the tundra. It does not necessarily occur in a given area every year. This species occurs around the globe in northern Europe, Asia, and North America.
Host Plants: Willow (Salix spp.), birch (Betula spp.), and poplar (Populus spp.).
Flight Period: Likely the longest lived adult butterfly in Canada. Overwintered adults emerge in April and fly as late as June. New generation emerges in July or August and flies until October.
Similar Species: None in Ontario.