National Moth Week Recap, 2015

Better late than never, allow me to share with you the experiences we had here in Colorado during National Moth Week, July 18-25. I participated in three events here along the Front Range, and all of them exceeded expectations in terms of public participation and excitement over the insects we encountered. While I approached two of these venues about doing Moth Week events, Bell Mead of the Mile High Bug Club carried out all the liaison and organizational work.

Watching the female sphinx moth lay eggs at Cheyenne Mountain State Park event

The first event was held at Cheyenne Mountain State Park, located just south of Colorado Springs, on July 18. Park staff arranged for us to set up at the camper services building, hoping to draw campers in the park, but there was enough publicity that people came from elsewhere, too (like "moths to a flame?"). One family even supplied their own lights and sheet. It turns out one of their children raises moths, and dad had to secure interstate permits to legalize the rearing of species not found in Colorado.

Can't beat the view of Colorado Springs from Cheyenne Mountain State Park © Bell Mead

The landscape surrounding the building is mostly grassland, with Gambel's Oak thickets and scattered mixed conifers. This diversity in flora produced a corresponding diversity of moths. Among the more spectacular specimens were a female sphinx moth, Smerinthus ophthalmica, which began laying eggs right on one of the sheets.

The sphinx moth laying eggs © Bell Mead

The public portion of this event ended around ten PM, but the Mile High Bug Club folks held an "after party," visiting illuminated outposts such as restrooms, self-pay kiosks, and the visitor center. Moths may be a "gateway drug" to a fascination with other nocturnal arthropods, and indeed we found many interesting beetles, true bugs, scorpions, a large centipede, and two "camel spiders" (non-venomous arachnids in the order Solifugae).

© Bell Mead

The second event was held Wednesday, July 22 at Hudson Gardens & Event Center in Littleton, Colorado, just outside Denver. Amanda Accamando, the Education and Volunteer Manager there, provided many supplies, creative publicity, and volunteer support. It paid off. We had thirty (30) attendees.

Visitors to the Hudson Gardens event © Amanda Accamando

We chose the "Hobbit Hole" as our station, located beside a long pond that we assumed would be a natural flyway for moths. Unfortunately, we were overwhelmed by caddisflies instead. The few moths that did make it to our sheets were interesting species, though, and no one felt the least bit disappointed given the myriad other insects that flew in.

Bell Mead helping a visitor photograph a moth © Amanda Accamando

Our finale was a repeat of a private event the Mile High Bug Club held last year in Rock Creek Canyon, southwest of Cheyenne Mountain State Park. Our co-sponsor was the May Natural History Museum, which boasts the world's largest, publicly-accessible private collection of insects and other arthropods. The Golden Eagle Campground and RV Park is also here, affording even more lit-up facilities after dark.

One of the light stations in Rock Creek Canyon © Bell Mead

We were thrilled to have moth guru Sam Johnson on hand to set up his own stations, and help us paint bait on trees. "Sugaring" for moths consists of slathering a thick mixture of fermenting fruit puree, stale beer or other alcoholic beverages, and brown sugar onto tree trunks. Many moths that don't come to lights will come to bait. Glowsticks attached to the trees helped us locate the bait stations after dark.

American Bird's-wing moth, Dypterygia rozmani, at bait © Bell Mead

No sooner had the sun gone down on this pine-and-oak forest habitat than in came the moths, plus Ten-lined June Beetles (Polyphylla decimlineata), enormous root borers (Prionus californicus longhorned beetes), and many other insects. Here's a video of part of the fun.

Male Ten-lined June Beetle

This year, the area experienced an outbreak of the Douglas-fir Tussock Moth, Orgyia pseudotsugata, but most were in the cocoon stage, so we weren't inundated. A few males showed up at the lights, but females are wingless and call males to them from their cocoons.

Douglas-fir Tussock Moth

The bait was effective, and drew at least one species of underwing moth, Catocala amestris, that Sam identified as being a new record for southern Colorado. Last year, Same collected Catocala delilah, another unusual species for the region at this same location.

Catocala amestris © Sam Johnson

We were so excited by the success of these three events that we held another one, this time at Bell's home near Garden of the Gods Park in Colorado Springs, on August 15. Despite thunderstorms raging around the city, her neighborhood remained mostly rain-free.

Mothing at Bell's place © Bell Mead

We even took a stroll up to the American Mothers Chapel at the edge of Rock Ledge Range, to see what came to the lights on that little white building. We saw several familiar moth species, but plenty of new ones, too, given the later date.

Maple Spanworm moth, Ennomos magnaria at Bell's place

I want to again thank Bell Mead for coordinating with personnel at all the event locations, securing lights and other equipment, and generally organizing everything. Additional thanks to Brian Kelly and Rick Baker of Mile High Bug Club for their assistance, too, and my wife Heidi for enjoying the same odd recreational experiences that I do.

We're already looking forward to National Moth Week, 2016, but we probably won't wait until July to start "mothing." After all, the IO Moth and other big, exciting moths emerge earlier than that.

Spring White

Fashion rules dictate that one cannot where white after Labor Day, but the Spring White butterfly, Pontia sisymbrii, need never worry. These pale insects expire long before that arbitrary deadline. Indeed, these are among the first butterflies of spring here along the Colorado Front Range, often appearing before the official date of the spring equinox.

Heidi and I have seen several specimens already this year, on March 9, along the Arkansas River below Pueblo Reservoir. I expect to see them any day now here in Colorado Springs.

These are wary butterflies that perch frequently but startle easily. Approaching one to take its photograph is usually an exercise in futility. Males are known to “hilltop,” flying along the tops of ridges and buttes to intercept females flying up from below. You can also find them in canyon bottoms, the topography funneling females into those areas.

Like most members of the family Pieridae, caterpillars of the Spring White feed on cruciferous plants: mustards and their cousins. Females deposit one egg at a time on the stems and foliage of host plants, especially hedge mustards (Sisymbrium spp.), tansy-mustard (Descurainia spp.), and rock-cresses (Arabis spp.). In some places in northern California, Brewer’s Jewelflower, Streptanthus breweri, produces orange spots that mimic the eggs of the butterfly. The female insect avoids those plants, since caterpillars are known to cannibalize each other when too many are on one plant (Pyle, 2002).

The caterpillars hatch from the eggs in roughly a week and begin feeding in earnest. The larvae progress through five instars (an instar is the interval between molts, first instar being what emerges from the egg), and older caterpillars are quite attractive as you can see in the image below, shot by Aaron Schusteff and borrowed from Bugguide.net

© Aaron Schusteff via Bugguide.net

At the end of the fifth instar, the caterpillar graduates to the pupa stage. The chrysalis is described as being mottled brown or black with a granular texture. While the chrysalids of most pierids are each suspended in a “girdle,” a belt-like strand of silk around the midsection and attached to the substrate at two points, the Spring White pupa lacks this feature. It attaches to the surface of the leaf, stem, or other object only at the tail end of its body. Hooks fasten into a tiny pad of silk to secure it firmly.

Some specimens have a nearly pure white upper surface

This butterfly ranges over most of the U.S. west of the Rocky Mountains, including the mountains of Arizona and New Mexico, spilling over the divide into extreme western South Dakota and the panhandle of Nebraska. It also occurs in south-central British Columbia. In Oregon and Washington it is found east of the Cascade range (and in the mountains of the Olympic peninsula in Washington).

Look for this species early in the season, from late February on through the end of June. It frequents foothills and higher elevations. It flies earlier than most whites, but pay attention to the dark pattern of veins on the underside of the hind wings to cinch an identification.

The Spring White may be a more accurate predictor of the arrival of spring than Punxsutawney Phil, the famed groundhog, at least here in the western U.S. Good luck getting the butterfly to pose for a photo opp, though.

Sources: Brock, Jim P. and Kenn Kaufman. 2003. Kaufman Field Guide to Butterflies of North America. Boston: Houghton Mifflin Company. 384 pp.
Lotts, Kelly and Thomas Naberhaus, coordinators. 2014. “Spring White,” Butterflies and Moths of North America.
Pyle, Robert Michael. 2002. The Butterflies of Cascadia. Seattle: Seattle Audubon Society. 420 pp.