California Sister (Adelpha bredowii)

California Sister Butterfly
Wing span: 2 1/4 - 4 inches (5.7 - 10.1 cm).

Identification: Upperside is brownish black with an orange patch at the forewing apex. White median band across both wings is broken on the forewing.

Life history: Males perch and patrol all day for receptive females. Eggs are laid singly on leaf edges; caterpillars feed on mature leaves. Young caterpillars make a long perch by extending a leaf vein with dung and silk. Partially-grown caterpillars hibernate.

Flight: Two flights from May-September.

Caterpillar hosts: Leaves of oaks (Quercus) particularly live oaks.

Adult food: Rotting fruit, aphid honeydew, sometimes flower nectar such as California buckeye.

Habitat: Oak-covered hills, groves, and stream valleys.

Range: Southern Oregon east to Colorado, south to southern California, Arizona, South Texas, and Mexico.

Conservation: Not usually required.

Management needs: None reported.

The Nature Conservancy Global Rank: G4 - Apparently secure globally, though it might be quite rare in parts of its range, especially at the periphery.

Photographs and text copyright by and adapted from US Geological Survey's Butterflies of North America.