Giant Swallowtail

© Dave Spier

With a wingspan of roughly five inches (give or take an inch), the Giant Swallowtail (Papilio cresphontes, syn. Heraclides cresphontes) is one of the largest butterflies in eastern and southern North America. Females are larger than males.

This butterfly species ranges from Arizona to the East Coast and from southeastern Canada to Texas and Florida with a population extension into California. In the south the caterpillars are sometimes considered pests in citrus orchards. In the north the larvae eat Prickly-ash (a shrub unrelated to ash trees, although the compound leaves have a similar appearance). Common or Northern Prickly-ash (Zanthoxylum americanum) is in the citrus family (Rutaceae) and sometimes called "toothache tree" because the bark was chewed to relieve tooth-ache. Although I've found prickly-ash locally, its core range is the upper Mid-west.

Giant Swallowtails are dark brown to black with rows of pale yellow spots near the outer edges of all the wings and another row straight across the fore wings. The rear wing "tails" have yellow centers. Small orange and blue spots on the inner wing edges flank the abdomen tip.

Look for these butterflies in open areas and scattered woodlands, a perfect description of our yard where the butterflies check our garden flowers for nectar. The photo, however, was taken beside the Manchester Gateway Trail along Canandaigua Outlet Creek in the Village of Manchester, NY. It was visiting flowers in the open area under the high-voltage power lines. The rest of the trail is mostly wooded floodplain with deciduous trees.

There are several broods per year in the north, but the timing is variable from May to August or September.

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