Bees sip honey from flowers and hum their thanks when they leave.
Rabindranath Tagore
The gaudy butterfly is sure that the flowers owe thanks to him.
The Oregon coast is very lucky to have a native butterfly species that is both colorful and spectacular.
The Oregon Swallowtail is part of a larger Papilionidae family that includes some of the largest and most beautifully colored butterflies in North America. North America has 40 species.
Territory
The Oregon swallowtail lives only in Oregon, Washington, Idaho, and south-central British Columbia. Swallowtail species can be found in the Arctic Circle south into Mexico. Most sightings in Oregon are along the mainstems and immediate tributaries of the Columbia, Deschutes and Snake Rivers.
There are over 550 butterfly species in this family. Most reside in tropic and subtropic regions. The Oregon Swallowtail may have originated there.
Food
Adults feed on wildflower nectar from thistles, balsamroot, phlox, daisies, asters, rabbitbrush, penstemon, milkweed, and dogbane. The larvae (juveniles) feed on tarragon sagebrush (also called wild tarragon or dragon wormwood, Artemisia dracunculus).
Swallowtail butterfly caterpillars feed on a wide range of plant families, and often depend on one of five families: Aristolochiaceae, Annonaceae, Lauraceae, Umbelliferae (Apiaceae) and Rutaceae. These plant families include toxic plants. Once eaten, the toxin makes both the caterpillar and butterfly also toxic which helps protects them from predators.
Predation
Oregon Swallowtails have wingspans up to 4-inches that sport a bright yellow with black-lined pattern and a ‘tail’ that extends off the back wing. The yellow wing markings of the Oregon swallowtail are brighter than the common swallowtail.
The tail is not required for flight, and may be sacrificed to escape predation. The hope is that the bird may ‘swallow the tail’ rather than a more critical body part and allow the butterfly to survive.
Several Swallowtails can also change their behaviors to help reduce predation. They will imitate the behaviors of other distasteful species, and several studies show females imitating males as a way to reduce predation.
Predators can include birds, wasps, spiders, and preying mantis, skinks, skunks and human collectors.
When to look
Look for Oregon Swallowtail butterflies in flight between April and September. Those seen early in the year are generally lighter in color than those seen later and blend well with the color of early plants.
Swallowtails are wary and strong fliers. This butterfly was selected as Oregon’s official insect on July 16, 1979, not only because it is a native but also because it has ‘Oregon’ in is common and scientific names. Oregon Swallowtail butterflies are a wonderful aesthetic gift.
REFERENCES:
–Oregon Dept. of Fish & Wildlife, Oregon Swallowtail Factsheet (https://www.dfw.state.or.us/conservationstrategy/docs/Swallowtail_factsheet.pdf)
–Butterfly Identification, Oregon Swallowtail (https://www.butterflyidentification.com/oregon-swallowtai.htm)
–EReference desk (https://www.ereferencedesk.com/resources/state-insect/oregon.html)
Wikipedia, Papilio machaon oregonius (https://en.wikipedia.org/wiki/Papilio_machaon_oregonius)