Alternate Common Name: Western Hairstreak.
This species ranges from southern British Columbia south to southern California, and east to Idaho and central Wyoming and Colorado.
It occurs in dry habitats such as chaparral, open woodlands, shrubby areas, and canyons of lower elevations.
Caterpillars eat the leaves of a variety of species, including buck brush
(Ceanothus spp.), oaks (Quercus spp.), mountain mahogany (Cercocarpus
spp.), chokecherry (Prunus virginiana), and serviceberry
Adult: Butterflies drink flower nectar, often from milkweed (Asclepias spp.),wild buckwheat (Eriogonum spp.), and buck brush (Ceanothus spp.).
Eggs are laid in the fall, overwinter, and hatch in the spring. There is only one generation of caterpillars each year. The caterpillar is equipped with a honey gland, also known as a dorsal nectary organ, which emits a sugary solution agreeable to ants. The ants feed on the solution and in turn protect the caterpillar from predators. Each caterpillar undergoes four stages of growth, called instars. Adults generally fly from June to early August. The tails of the hindwings of the butterfly resemble antennae and can act to fool predators into biting the wrong end of the butterfly, allowing it to escape.
Males perch in the tops of trees most commonly at the tops of hills to wait for receptive females, and sometimes actively patrol for them. This behavior is called "hill topping". Eggs are laid in the hollow portions of the bark of host plants, typically in clusters of two to four which are then cemented together by the female.
|Idaho Status:||Unprotected nongame species.|
|Global Rank:||G4; population levels are secure, but may be of concern in the future.|
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