Great Basin Butterflies

By SFI butterflies instructor Dana Ross

A visit to Steens Mountain and the Alvord Desert is always worth the time and effort. This past July, I taught a new 3-day course for the Siskiyou Field Institute (SFI) on the butterflies of the region based at Malheur Field Station.

DAY ONE. On Friday afternoon, we gathered inside the main Malheur Field Station building for an introductory presentation on the area and its butterflies. Afterwards, we briefly explored the field station grounds (with nets of course!) for a first look at the local butterflies of summer. Wandering out the long driveway we encountered a plethora of white butterflies on the flowering roadside shrubs and forbs. Among them were large numbers of the Western White and the occasional Checkered White, a somewhat sporadic Oregon visitor that is not seen every year. Also in the mix were a few Small Wood-Nymphs, Queen Alexandra’s Sulphurs and a fresh Coronis Fritillary.

DAY TWO. After breakfast Saturday morning we began our butterfly adventure with a first stop at Blitzen Crossing. While there we encountered Two-tailed Swallowtails and Western Tiger Swallowtails as well as the silver and greenish underwing patterned Callippe Fritillary and the palest subspecies of the Zerene Fritillary. Each new species was placed in a viewing jar and passed about.

After making our way up the long, sage-dominated ridge between the Little Blitzen and Big Indian gorges, we arrived at our lunch stop. The landscape was rocky and somewhat barren so soon after snowmelt, yet freshly eclosed tiny Buckwheat Blues and grass green hairstreaks shared the landscape there with worn, post-hibernant Milbert’s Tortoishells and equally dilapidated Zephyr Anglewings . After lunch we turned south, parked, and made the short, steep walk to the summit of Steens Mountain (9,733 feet). From there we enjoyed an exquisite view of Wildhorse Lake, nestled within the large cirque below us. All around us small, blooming “cushion buckwheats” hugged the ground, offering nectar and refuge from the wind for yet more tiny Euphilotes. And then…the day’s second unexpected encounter. A fresh hilltopping Indra Swallowtail suddenly appeared. I moved into its path and when it came within reach I swung hard…and missed! I followed it as best I could for about 100 feet before watching it suddenly drop to the ground. Apparently, I had not spooked the butterfly and it had spotted a favored nectar flower that it could not resist. I quickly moved within reach and netted this rarely seen Steens Mountain species. My declaration of victory caught the attention of the class, allowing for another show and tell opportunity.

There was one butterfly that I had promised to the class that we had yet to locate – the fiery orange Lustrous Copper . The season was too early up high where I had seen it on previous visits. After a quick stop at the Kiger Gorge Overlook, we continued our counterclockwise loop via Fish Creek Road. Before long, we encountered a small headwater stream in a subalpine meadow adjacent to an ancient grove of aspen trees. Several species of blues, including our first Silvery Blue mud-puddled, while Common Ringlets , Field Crescents , worn Juba Skippers and a fresh Anise Swallowtail did their best to elude capture. And then there was the cry of “I got one!” from a member of the group. The Lustrous Copper could now be appreciated and checked off the list. We made a final stop at Lily Lake. The surrounding meadow hosted many of the butterflies that we’d seen previously that day . It had been a long day and a good one. We’d observed over 40 species of butterflies, including some “firsts” for virtually everyone in the group.

DAY THREE. Recent reports suggested that the Alvord Desert area on the back side of Steens Mountain might still be a good destination for the class. Starting at the north end (Folly Farm Road), I pointed out the “type locality” for Sullivan’s Sulphur before leading the small convoy to our first stop at Mann Lake. It was mid-July and the Alvord Desert was heating up and drying out quickly. Yet since the retreating lake had left a well-watered periphery that hosted the larval hostplants for the Melissa Blue and Ruddy Copper , we found both butterflies to be fresh and abundant. A variety of pierids – including Orange Sulphur, Queen Alexandra’s Sulphur, Becker’s White and Checkered White – moved through the area, pausing only occasionally and briefly to take nectar from scattered clumps of blooming thistles. I hoped that the Pike Creek Trail might offer us the requisite moisture and flowers for decent butterflying, so we worked our way slowly up the trail in the intensifying mid-day heat. It ended up being too dry, too hot and too uphill, so we cut the hike short. The nine species of butterflies there included nothing new, although cicadas, cicada killer wasps and Pacific Spiketail (Cordulegaster dorsalis) dragonflies kept things interesting.

Just south of the Catlow Valley Road – a route that would take us back to Frenchglen and the field station a bit later that afternoon – is the tiny town of Fields. The general store and gas station provide essential resources for the outdoor explorer. We gassed up and sat in the shade while we consumed fruit popsicles. The massive milk shakes are even better and go well with cheeseburgers and fries, but we didn’t have the 30-40 minutes it might take to have them made for everyone since we had one more stop on the itinerary. Arizona Creek sits a stone’s throw north of Denio, Nevada, on the east slope of the Pueblo Mountains. It and the adjacent canyons offer the lepidopterist a chance to see an unusual hybrid population of Lorquin’s and Weidemeyer’s Admirals, known as Friday’s Admiral. Individuals run the gamut from nearly pure Lorquin’s to nearly pure Weidemeyer’s, with everything in between. A bit of creekside “hunting” resulted in the capture of two individuals from each end of the spectrum. Weidemeyer’s Admiral or Friday’s Admiral at the far end of the hybridization spectrum?

Friday Admiral hybrid
Photo by Linda Kappen

My impression was that everyone thoroughly enjoyed the course – a bit of desert heat and some locally pesky mosquitoes aside. The Siskiyou Field Institute is offering this course with an additional day to explore the area, July 10-13, 2020 under the title of Great Basin Butterflies. It will once again be my pleasure as class instructor to introduce participants to the area and its butterflies as we explore Steens Mountain and the surrounding area.

 

Leave a Comment