Click here for a list of species seen on this trip
horseshoe mountain

The Colorado Rockies offer clear skies and spectacular scenery as backdrops to some of the most wonderful butterflying imaginable. On this tour, at the peak time for diversity in the region, we should see clouds of butterflies, of around one hundred different species, nectaring in flower-filled meadows, set amidst breathtakingly beautiful snow-capped peaks.  Contributing to our experiencing this diversity is the great variety in elevation of the locations that we will visit.  Certain species are restricted to various elevational ranges and, even though we will be traveling in the summer,  we will be able to find some “spring” species at higher elevations.  In addition to thrilling to the exceptional diversity of butterflies, it will be difficult to ignore the exceptional displays of wildflowers.

Day 1. Friday. The tour begins this evening at Denver airport.  Night in Denver

Day 2. Saturday. One of the best known and most productive parks in the Denver area is Apex Park. This 530 acre county park is in the Front Range, a north-south mountain group that forms the foothills of the Rockies.  With an elevation of 6200 ft. at the mouth of the canyon and 7200 feet at the highest point in the park, we’ll get acclimated to the higher elevations to come.  More than 120 species of butterflies have been found here, but not at one time.  If past experience is a guide, many species should be abundant during our visit.  These may include red-spotted, white Phoebus Parnassians, the U.S. counterpart of the famed European apollos, brilliant Blue Coppers, Behr’s Hairstreaks, Boisduval’s Blues, Aphrodite and Atlantis Fritillaries (we’ll check out their eye color), and Common Wood-Nymphs.  Especially at small seeps and water crossing, we have good chances for Dotted Blues, Arrowhead Blues, Melissa Blues, Nais Metalmarks, Satyr and Hoary Commas, and Wiedemeyer’s Admirals, Russet Skipperlings, and Green Skippers.  We’ll hope to see a rare Ottoe Skipper.  Night in the Denver area.

Day 3. Sunday. This morning we will drive southwest out of Denver, stopping at a number of key butterflying locations as we go.  Traveling along the north fork of the South Platte River, and then over Kenosha pass (10,000 ft.), we’ll butterfly high mountain bogs searching for Frigga Fritillaries.  We’ll end the day at the town of Fairplay. If time permits, we may take the road toward Horseshoe Mountain Park. Night in Fairplay

Days 4 and 5. Monday-Tuesday. We will spend these two days high in Horseshoe Mountain Park, an eerily beautiful environment with immense glacial cirques, extensive rockslides and alpine meadows.  Here we have seen many hard to find alpine specialties.  Burnt-orange Mead’s Sulphurs may be swirling in open meadows, challenging the patience of photographers and we have another chance for Frigga Fritillaries. We may see elusive Rockslide Checkerspots and inky-black Magdalena Alpines skitter across rockslides a rather hazardous environment for terrestrial creatures. Polixenes Arctics may be found on high on grassy knolls, while Melissa Arctics prefer rocks. Grizzled Skippers and Draco Skippers may stay long enough to afford good looks.  Nights in Fairplay.

Day 6. Wednesday.  Today we will head north, stopping to butterfly the vicinity of Loveland Pass at 12,000 ft. Here we hope to find Freija Fritillaries and the unusual ‘brucei’ form of Common Alpines as well as a good variety of other high altitude butterflies. Night in Central City.

Days 7-8. Thursday-Friday. We have two full days to explore fabled Gilpin County which offers dense forest, rocky peaks, aspen-filled meadows and, oh yes, butterflies.  The Gilpin County NABA 4th of July Count holds the record for the most species on a United States count – 111 species.  We have reasonably good chances of seeing Indra Swallowtails and, depending upon the vagaries of the year, late flying Large Marbles.  Uncommonly seen Scudder’s Sulphurs and lavishly colored Thicket Hairstreaks are real possibilities, as are Greenish Blues, Arctic Blues, Coronis Fritillaries, Arachne Checkerspots, Silvery Checkerspots, Small Wood-Nymphs, Ridings’ Satyrs, and Taxiles Skippers. And, something like 98 species more!  Thursday night in Central City.  Friday night in the Denver area.

Day 9. Saturday.  Trip ends this morning at the Denver Airport

Leader will be Jeffrey Glassberg.

Other Considerations.  Participants on this trip will spend a fair amount of time at high elevations, from 7,000 to somewhat over 12,000 ft. 

Cost of the trip is TBD/person from Denver. Cost includes double-based accommodations, all meals (except, because of staggered arrival times, dinner the first night) and soft drinks, ground transportation, airport transfers, tour leader fees and entrance fees.  Not included are alcoholic beverages, laundry services, and other items of a personal nature.  Single supplement is TBD.

Click Reservations for a Reservation Form.



Apex Park
Blue Copper
Magdalena Alpine

Apex Park in flower

Blue Copper
Magdalena Alpine
at Horseshoe Campground
Phoebus Parnassian
Phoebus Parnassian

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Colorado Rockies and the Front Range

early July