A small group of intrepid butterfly watchers made their way up the nasty road to the Slate Peak/ Harts Pass area around the first of August.  As we puzzled out how to social distance and appropriate mask wearing strategies in the fresh mountain air, it became evident that the butterflies and other insects did not care. In the bright sunshine at 7440’ elevation, we were treated to early morning visits from the stars of the show. We were able to get great photos of Melissa Arctics, Astarte Fritillary and a little later even the Lustrous Copper.

We identified a total of about 28 species over two days.   The wildflower season was in full swing with multiple nectar sources from the summit down into the lush meadows clear down to Harts Pass. The meadows were a little drier than years past but still afforded plentiful choices for butterflies. Especially common in the meadows were Vidler’s Alpine and Mountain Parnassians.                  

Checkerspots appeared to be especially abundant at all levels on the mountain.

The weekend started very well when we were able to net the Melissa Arctic. These butterflies are rarely seen in Washington as they are more common to the mountain tops of Canada. It was my first time seeing the Melissa Arctic in eight trips to Slate Peak.

These fast flying butterflies have a two year life cycle which means it took me sixteen years to successfully see them in Washington! These butterflies glide up the warm scree slopes and when they settle down on the warm rocks to bask in the heat, their cryptic coloration makes them all but invisible. (see photo in Gnum Vol 21 No. 3)

The equally elusive Astarte Fritillary also graced us with a visit. These are members of the “Lesser Fritillaries” even though there is nothing less exciting than seeing these members of the genus Boloria. I sat on a pile of rocks along the ridge to the northwest of the summit, eagerly watching for the Melissa Arctic. I would see a few of these orange and black butterflies flying low in the rills and riffles of the rock slopes. They flew low to the ground (perhaps gathering heat radiating off the rocks) and would make their way near the ridgeline and abruptly turn around and glide back down – always just beyond reach.

The Melissa Arctics seemed to be what we call hill toppers as they were always near the actual rocky top that was flattened off in the 1950’s for a radar dome. The Astarte was found – but rarely netted – all along the scree ridges that spread out from the summit. They seemed to like the warm eastern slopes out of the mainly westerly breezes.

The Astarte flew over pockets of flowers and patches of scattered greenery. They interacted with the Checkerspots, Anna’s Blues and Mormon Fritillaries. As they chased each other over the edge of the ridge, as they sped past it seemed we could only net the checkerspots and Mormon Fritillaries. We would check to see if they were Anicia Checkerspots or their look-alike cousins, both editha and hoffmanni – were also flying. With identity confirmed, the more common butterflies were quickly released to continue their patrol, others got their pictures taken first!

With our luck of seeing these rare creatures from the North, we perhaps stayed too long at the upper reaches of the mountain and not enough time below in the meadows. Perhaps with giving the meadow habitat a little more time our species count would have risen but the treat of seeing the truly rare species kept us more than enthused. A side benefit to staying up high was the several hundred Pacific Crest Trail hikers we avoided in the time of Covid 19. And where there are lots of hikers, there are even more horseflies to be endured than we faced upslope. Yes. Slate Peak did not disappoint.

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