Pontia beckerii

Becker's White

Family: Pieridae · Class: Insecta · Order: Lepidoptera

Becker's White is a small to medium-sized butterfly in the family Pieridae, with a wingspan ranging from 35 to 50 mm (1.4 to 2.0 inches). Males display bright white wings with black markings along the wing tips and outer margins, while females are typically larger and show more extensive black markings with yellowish coloration on the undersides of the hindwings. The species can be distinguished from similar white butterflies by its distinctive wing pattern and the presence of gray-green scaling on the underside of the hindwings with dark veining. Becker's White ranges from British Columbia and Alberta south to Baja California, occurring east of the Cascades and Sierra Nevada mountain ranges, and extending east and south to western Montana and New Mexico. In California, the species is found primarily in the eastern regions of the state, including the eastern Sierra Nevada foothills, Modoc Plateau, and desert regions. The distribution reflects the species' preference for arid and semi-arid environments typical of the Great Basin and Mojave Desert ecosystems. This butterfly inhabits open, arid landscapes including desert scrublands, sagebrush communities, juniper woodlands, and disturbed areas such as roadsides and agricultural edges. The species occurs at elevations ranging from sea level in desert regions to approximately 2,400 meters (7,900 feet) in montane environments. Becker's White demonstrates adaptation to harsh environmental conditions, including temperature extremes and limited water availability characteristic of western North American desert ecosystems. Becker's White is multivoltine, producing two to three generations per year depending on local climate conditions and host plant availability. Adults are active from March through October, with peak flight periods typically occurring in spring and early summer. Males exhibit patrolling behavior, flying low over potential breeding sites in search of females. Females lay single, pale yellow eggs on the leaves and flower buds of host plants. The larval stage feeds exclusively on plants in the mustard family (Brassicaceae), including various mustards (Brassica species) and hedge mustard (Sisymbrium species), as well as bladder-pod (Isomeris arborea) in the caper family (Capparidaceae). Larvae are pale green with dark stripes and complete development through five instars before pupating. Becker's White does not currently hold federal or state conservation listing status. The species appears to maintain stable populations across much of its range, benefiting from its ability to utilize both native and introduced host plants. However, localized populations may face pressure from habitat loss due to urban development, agricultural conversion, and invasive plant species that compete with native host plants. The butterfly's association with disturbed habitats and introduced mustard species has allowed some populations to persist in modified landscapes, though long-term monitoring data are limited for assessing population trends across the species' extensive range.

Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, and more.