The scientific name of the California sister butterfly (Adelpha californica) until recently was Adelpha bredowii or commonly, Bredow’s sister. The newer classification separates the California sister from similar butterflies based on their different distributions. This “sister” inhabits mountain forests and oak woodlands, especially near streams and canyons, in California, Oregon, Western Nevada and Northern Baja. The few sightings in Washington State are believed to be, at this time, vagrants.
The wings of a California sister are blackish brown. The forewings have a broken, narrow white median band and a large, orange apical (near the tip) patch. The hindwings also possess a white median band. Both the fore and hind wings have vertical bluish bands along the edges and a blue and orange pattern near the body. Because California sisters are unpalatable to predators, several other butterflies mimic their pattern, including Lorquin’s Admiral.
The female lays single green eggs near the tips of the upper surfaces of oak (Quercus) leaves. The caterpillars go through four larval stages (instars) while feeding on oak leaves. The different caterpillar stages vary in color and markings. Partially grown caterpillars hibernate over winter. Adults sip nectar from rotting fruit and occasionally feed on flower nectar.
At some point someone decided that the black and white coloration of the California sister resembled a nun’s habit, thus the common name “sister”. This theme is continued in the genus name; Adelpha derives from the Greek and means sister.
This picture, taken along the Falls Loop at McArthur Burney State Park (Shasta County CA), has a little background story. While waiting to meet Leonard I saw this California sister and began to photograph it. A young girl about nine years of age came up to me and asked about the butterfly. What a delight to have a young person take their attention away from their electronic devices. I began to tell her about the butterfly when she poked at it. The butterfly flew about fifteen feet away and landed with its wings spread – open wing photo op! The little girl ran ahead of me, again poked at it and the California sister flew high into an oak, much too far away for a picture. My “friend” pointed to the tree top, said, “There it is, you can take a picture.”, and skipped away. And people wonder why I like to hike and photograph alone.