Western Tailed Blue
The Western Tailed Blue is one of several species of butterfly that we are inexorably losing from southern Vancouver Island. Although it is still to be found, sparsely, north of the Malahat, it used to be common in Victoria, from which it is probably now completely absent. Eggs are laid singly on the flower stalks or calyces of Lathyrus sp. The caterpillars feed on the flowers, then they go into diapause, and winter is spent as a caterpillar. Beginning botanists may have difficulty distinguishing between peas (Lathyrus) and vetches (Vicia), but in my experience the butterfly has no difficulty and has a decided preference for Lathyrus.