A western tiger swallowtail butterfly on western columbine near Halfway Camp on the Vivian Creek trail on Mt. San Gorgonio.

A section of the trailing edge of the swallowtail's right hindwing is missing -- probably the result of bird predation. This did not seem to affect the butterfly's flight. It still nimbly flittered from flower to flower.

From Saturday's San Gorgonio Mountain - Falls Creek run.