The Sternitzky Effect
Updated: Aug 4, 2020
The Mountain Parnassian is a denizen of steep, high elevation meadows with rocky outcroppings that support its host plants in the genus Sedum (Stonecrop). It was to some of those high, steep meadows near Mt. Ashland in Jackson County, Oregon that I headed last week to search for and hopefully photograph Sternitzky's Parnassian.
Robert F. Sternitzky was a lepidopterist and illustrator from San Francisco, who mostly collected in California and Arizona in the 1930's. He was recognized posthumously for his contributions to the knowledge of southwestern butterflies by having several butterfly species and subspecies named after him, including a sub-species of the Mountain Parnassian that occurs in Oregon and California. That lovely insect is Parnassius smintheus sternitzkyi, or Sternitzky's Parnassian. In Oregon, the Mountain Parnassian occurs in the Blue Mountains of NE Oregon, and in the opposite corner of the state in the Siskiyou Mountains near the California border.
From several previous experiences photographing Mountain Parnassians in Oregon, I learned that finding them was the easy part. Photographing them, on the other hand, was another story. On a typical warm sunny day, Mountain Parnassians constantly fly in seemingly random, criss-crossing patterns across steep meadows that are challenging for humans to navigate. On these rocky slopes, the notion of chasing one of these strong fliers is laughable, and would likely land me in the hospital. They do, on occasion, venture off these steep meadows into flatter terrain, sometimes next to a trail or road, where, with great luck, they will perch long enough for a photo. My friend Rob Santry has had such luck, but I wasn't sure I could count on that.
Since I had only two days to get these photos before making the 3 1/2 hour drive back to Eugene, Oregon, I decided it might not be the best approach to bank on getting lucky along the trail or the road. So, as I surveyed the entire area to get an idea of where the parnassians were flying, I stopped at each meadow and watched their flight patterns for several minutes. I was hoping to see some favored spots where they would perch or favorite patches of flowers where they would stop to nectar.
In most of the meadows, I couldn't see any particular pattern, but in one them, I noticed that as they made their zig-zag traverses of the meadow, they often lingered near several adjacent patches of coyote mint (Monardella villosa). Knowing that coyote mint is an effective butterfly magnet in many of the high places in Oregon, I started to watch just that spot. Watching for a good while, I did see a couple of parnassians stopping for nectar in that patch, whereas I hadn't seen them stop anywhere else in the area.
I carefully worked my way across the slope from the nearest trail and sat down on a rock, ensuring that I minimized my impact on the meadow's vegetation. And I waited. It took about 15 minutes before the first parnassians began to fly near me. If I so much as turned my head to watch them fly, they would zip away to another part of the meadow. I could see this was going to be a very "meditative" experience, in which I would be sitting very still, patiently waiting with my camera ready and pre-aimed and pre-focused at the most likely coyote mint patches.
After another 10-15 minutes of sitting still, it happened. A parnassian came to the coyote mint I was aimed at, and stopped to nectar. Woo-hoo! Maybe this was going to work! And work it did. Once that first parnassian "tested the water," others came also. I probably had about 15 opportunities to photograph them from about 1:30 - 2:30 pm, by waiting for them to come to me. Often there would be grass or flowers blocking the view, but several times they were unobstructed. One parnassian even came and landed one a coyote mint plant just 2 feet away from me, almost too close for my camera to focus!
On this warm and sunny day, the parnassians nectared only with their wings folded up, which gave me good chances for photographing their lovely ventral pattern of white, black and red. I'd also hoped for shots of them basking with their wings spread, but I only saw this once in two days, at about 8:30 am and only for a couple of seconds. It was way down the slope from me, so there was no chance for a photo there. That basking shot will have to wait until next year!
One of the other "specialty" butterflies of this area is the Sooty Hairstreak, which in Oregon also occurs just in this small area adjacent to the California border. These little, dark tailless hairstreaks fly quickly around and above patches of manzanita on the tops of the ridges above where the parnassians fly. They use lupines as their hostplants, but for some reason, they seem to prefer hanging out on and around the manzanita shrubs. They seemed easiest to find early and late in the day, but were scarce in midday. In the morning sun, I found them basking with their wings folded up.
The Great Basin Fritillary, Speyeria egleis, is another favorite butterfly that I often see in this area. In this area, the subspecies matooni is relatively common, and that was the dominant greater fritillary that I saw on this trip. They were also drawn to the coyote mint, but landed there even less often than the parnassians. The photo above was of the only one that landed to nectar during my parnassian stake-out.
The dry, flatter ridge tops where the Sooty Hairstreaks and Great Basin Fritillaries fly feature an abundance of sulphur flower buckwheat (Eriogonum umbellatum), which attracts the Summit Blue, Euphilotes glaucon. This attractive little blue is found throughout most of Oregon's mountainous areas where sulphur flower buckwheat grows. In this genus of blues, identification is primarily based on identifying the species of buckwheat that they are associated with. In terms of their field marks, the Summit Blue tends to be darker below than several of the other Euphilotes blues found in Oregon, and I have found them to be markedly so in some areas (e.g., northern Klamath County).
In addition to the meadows along Mt. Ashland Road, I also explored the meadows around and along McDonald Creek, several miles west of Mt. Ashland itself. This lovely (and more moist) area had a different array of butterfly species than the drier south-facing slopes I'd been in, including a couple of lovely Buckeyes, Pacific Fritillaries, Greenish Blues and Sonora Skippers.
One of my general observations on this trip was that the overall numbers of butterflies and the diversity of species seemed noticeably low for this time of year for this area. I have observed that same pattern on nearly every site I have visited in western Oregon this summer. Perhaps it was that cool, wet spell we had in the spring. Based on my observations this year, and in other years when unseasonably cool and wet weather occurs in spring, it seems as though the butterflies in the affected areas emerge from their chrysalides over a longer period of time than in years with more typical spring weather. Has anyone else noticed this? Or perhaps someone has studied this as an (epigenetic?) adaptation to climate variability? If you know of research in this area, I'd love to hear about it.
Over two days in the area west of Mt. Ashland I saw these 29 species: