Butterflies everywhere in the air! so many you have to drive about 5 miles an hour, letting the current of your progress gently push them out of the way. That’s how it was one morning last week, on the paved forest road where we often walk. By 3 pm it would be 100°. Though there were still wildflowers in bloom, these butterflies seemed not to be feeding, but mostly just flying and chasing one another. Breeding season? One did land for a moment on Dan’s finger and another swooped at it aggressively, over and over.
California Sister butterflies (Adelpha bredowii), ventral view.
As before, in a different location on this road, we saw scores of the California Sister butterfly (Adelpha bredowii) but this time none of the Lorquin’s admiral (Limenitis lorquinii) seen then. Swallowtails were present too, like sunlight in flight, but in small numbers. Unlike the others, the swallowtails never lighted for long either on vegetation or on the road, where the California Sisters clustered to get minerals from visible animal scat or from remains too small for us to see.
California Sister butterfly, dorsal view, on the road.
This ant was pulling along the body of a California Sister butterfly. It would move the butterfly an inch or two, then stop and scurry around looking (I thought) for a more effective place to grab on.
The swallowtails never let us get close enough for a really good look or photo, and we may even have seen more than one species. Dan, whose eyes are better, says that most were a pale yellow. the others brighter. Of the three found in our area, one is a species called the Pale Swallowtail (Papilio eurymedon) that uses Ceanothus spp. for its larval host plant, and Blueblossom ceanothus (Ceanothus thyrsiflorus) is a common flowering shrub here. Very pretty too, growing to 6 feet or more in height and flowering in varying shades of blue and lilac. Most are past their peak of bloom now, beginning to fade or entirely withered; these photos are from June.
The British biologist J. S. B. Haldane was engaged in discussion with an eminent theologian. ‘What inference,’ asked the latter, ‘might one draw about the nature of God from a study of his works?’ Haldane replied: ‘An inordinate fondness for beetles.’ Indeed, of the 1.5 million described species on the planet, 350,000 are beetles, more species than in the entire plant kingdom. So I didn’t even try to identify the mating beetles in the photo above, but Dan picked up Insects of the Pacific Northwest (by Haggard and Haggard) and found them easily: Anastrangalia laetifica, the Dimorphic Long-horned Beetle! The female’s red wingcovers are visible on the right side, beneath the male’s all-black back.
This is the Pale Swallowtail, below. [Photo by Franco Folini, from flickr]
Different life stages of the Pale Swallowtail caterpillar are shown here, and for the Anise Swallowtail here. Caterpillars can have quite different appearances, as they pass through successive moults (stages called instars), and so the one illustrated in your field guide for a given species may not look at all like the one you find.
The other Swallowtails likely to be seen here in Southwestern Oregon are the Anise Swallowtail (Papilio zelicaon) and the Western Tiger Swallowtail (P. rutulus). Oregon’s state insect is the Oregon Swallowtail (P. oregonius, sometimes called P. bairdii) but it’s found in the dry sagebrush canyons of Eastern Oregon and Washington along with its caterpillar host plant Tarragon or Dragon’s-wort (Artemisia dracunculus). Our culinary tarragons are varieties of this same species.