Science just won’t stand still. No sooner had we settled into a current picture of our butterfly fauna in The Butterflies of Cascadia, than two more species came to light.

The first had been predicted for discovery in the near future. Introduced ca. 1910 in Ontario, the European Skipperling (Thymelicus lineola) has been spreading ever since. Overwintering as an egg (unusual in monocot skippers), and favoring timothy as a host plant, the butterfly can easily be transferred with loads of hay. Not only does it spread along an advancing front, but new colonies can hopscotch across the countryside, hitching a ride on hay trucks. At least two prior introductions were known in British Columbia, and Merrill Peterson had seen them north of the border along the freeway. So on Friday, July 12, Thea Pyle and I investigated several sites along the BC-WA line in search of the Essex Skipper, as it is called in the UK. Failing to find it in the nectar-rich but close-cropped Peace Arch International Park, we extended our search eastward.

Just east of Blaine, D Street crosses a major north-south powerline. Rights-of-way, if not sprayed, may furnish excellent butterfly corridors. As soon as I left the car, I saw the first skipper, and Thea — after a run-in with a cable across the access road — netted it. This was apt, since she had previously found the first European Skipperlings in both Idaho and Montana in 1991. There were hundreds on the wing, all fresh males, some still drying wings, so we’d arrived early in the flight. They nectared on white clover, hawkbit, bramble, and other weedy flowers, and fluttered slowly. While it does have a higher gear, this species flies much more weakly than most tawny skippers. Compared to the Woodland Skipper, so common in the late summer and fall, T. /i11eola appears about half-size and half-speed. We found individuals east through the berry fields and pastures to Sumas and south to the Nooksack River northeast of Bellingham, so the colonization has already taken in a good chunk of northwestern Whatcom County. I suspect it may reach the Everett-Seattle area within three to five years.

The next addition, the Queen (Danaus gilippus), came in triplicate.  The only previous

Cascadian Queen had been spotted by Dana Ross in Harney Co., OR, in August, 1999. The first of three Washington records was spotted and photographed by writer Rob McNair­ Huff on the afternoon of August 18, 2000, as it visited a spent mullein plant and then nectared on a flowering shrub in his North Tacoma yard. Rob later mentioned his find to Idie Ulsh, who encouraged him to report it, thus establishing the state record. Lepidopterist Dennis Strenge netted a second Queen, a slightly worn male, while monitoring Monarchs among showy milkweed in Leslie Groves Park along the Columbia River in Richland on July 27, 2002. Then Charles Rogers netted a fresh female on August 26 — also in Leslie Groves Park. Since these were too far removed in time to be siblings, at least two generations of Queens must have occurred there this year: July immigrants with August offspring, or perhaps a June immigrant yielding two broods. How should we regard these new arrivals, one an alien, the other an exotic stray? Queens are not normally (or legally) used for commercial release; the Tacoma one might have escaped from a butterfly house, or have come up the coast or the Willamette-Puget Trough. The Richland Queens may well have arrived under their own steam via the Snake River, which Monarchs use extensively. The incidence of northeastern Queens is increasing, and we may see more here as summers grow hotter. As for the European Skipperling, I find it a positive addition — unlikely to harm native fauna or flora, attractive, interesting, and capable of extreme abundance such as we seldom see. The Washington butterfly list now stands at 147, more or less. Maybe we’ll hit 150 yet!

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