Skipper ID

Every fall these pretty blue beauties show up in our yard. They flutter away as quickly as they land, but one day I was able to snap this photo. Can you tell me what they are?

—Teresa Kollmar, Grandview, Washington

Tom: You've discovered the common checkered skipper, a butterfly that has two broods—one in spring and another in late summer and early fall. The butterfly's blue appearance comes from long, bluish hairs on the inner part of the wings. The species prefers fields and pastures with low-growing mallows, where it feeds. The caterpillars of this butterfly make leaf nests by rolling or attaching a group of leaves together with silk near the top of mallow plants. The nests are fairly easy to find. If you carefully look inside, you will see the greenish caterpillar, with a dark head and covered with short, whitish hairs. The caterpillars will winter fully grown in these leaf shelters.