California sister butterfly (Adelpha californica)
This week we’ll meet another pretty flitter who only lives close to home. Meet the California sister butterfly (Adelpha californica).
Their limited range starts in Baja, Mexico and goes up to Portland, Ore. Rarely one is found in western Nevada, but those are considered “strays.”
In Oregon, the most concentrated populations of California sisters are found right here in our southwestern area.
California sisters live in foothills and mid-elevation mountains in oak woodland and mixed coniferous forests, often along the edges of woods or in riparian canyons with small streams. Our area is chock full of habitat like that.
The one thing California sisters need is oak trees. We have three main species growing in our area that the sisters love: California black oak (Quercus kelloggii), Oregon white oak (Quercus garryana) and canyon live oak (Quercus chrysolepis).
Why do California sisters need oak trees? Because oak is the only food plant for their caterpillars. The ‘pillars are especially fond of canyon oak, but will chow down on any number of oak species found in their range.
Adult California sisters have a unique diet too. You won’t often find them flitting from flower to flower; they prefer rotting fruit. They also eat lots of minerals from mud and damp moss. If you recall, this is called “puddling.” You can see why they enjoy living by streams.
In Oregon California sisters will have two broods per year, so you can see them on the wing anytime from June through October. Further south they are active earlier and have up to three broods from April through October.
The first sisters to emerge in late spring or early summer overwintered in chrysalis form from eggs laid the previous fall. Their young will go through an entire life cycle during the summer months and lay eggs which will become the following spring’s early fliers.
California sisters lay small, round, green eggs singly on individual oak leaves. It takes approximately 65 days for the entire cycle of egg to ‘pillar to chrysalis to adult. Sisters face a lot of dangers along the way from becoming a snack for another critter to being parasitized by a fly or a wasp.
California sister ‘pillars are well camouflaged in shades of green, brown and tan and very spiky looking. This goes a long way to deterring would-be predators. Adult sisters may look delicate, but you don’t get to become a grown-up butterfly unless you’re tough.
Sisters are in the Tribe Limenitidini which includes admirals, sisters and sailors. The only similar-looking butterfly in our area is the Lorquin’s admiral. Lorquin’s have a less defined edge to that “pop” of orange on their 4wing tips and they lack the beautiful blue and red markings on the inside of the upper wings.
Despite their similarities, Lorquin’s and sisters aren’t competitive. They have different life cycles (Lorquin’s have only one brood per year) and different food choices as both caterpillars and adults.
Adults of both species like to catch some rays by basking high up on out leaves of trees and at that distance it can be easy to confuse the two.
So this spring and summer, try to get a good, close look at these black and orange beauties and you’ll know if you should salute an admiral or say “hey” to your sister.