September is a great month to catch the flight of butterflies in red rock canyons or in mountain meadows and summits as the males patrol these hilltops in search of females. This enjoyable butterflying experience is enhanced with distant mountain views, scenic redrock backdrops, and colorful late-summer wildflowers.

Over 250 butterfly species have been recorded in Utah, even though southern Utah represents a bit of a data gap because it has not been surveyed as extensively as other areas in the state. Reporting sightings to various community-driven databases such as iNaturalist or BAMONA, Butterflies and Moths of North America, are highly encouraged.

Here are just a few of the many butterflies that hikers might encounter on a September hike.
The mourning cloak butterfly, a large dark butterfly, is the Utah State Butterfly. Wide-ranging, the mourning cloak is found in wooded habitats because they feed on tree sap. The common name is derived from the dark wings resembling a heavy woolen cloak that a mourner might wear to a funeral in olden times. A tannish border with small blue dots offsets the dark wings.

Amazingly, these butterflies overwinter as adults, called the “imago” life stage. They find cracks and crevices in old barns, under tree bark, and other protective confines. To avoid freezing, the butterflies produce special chemicals in the circulatory system called cryoprotectants which act like antifreeze agents to protect the butterflies.

Probably the best-known butterfly US-wide is the monarch which shows up in Utah in July. These butterflies are orange with black lines and are fairly large. Tagging projects occur across the region where a small white dot with an identification number is affixed to the underside of a wing. This helps researchers track the movements and survival rates of these milkweed-dependent butterflies. Recently, the U.S. Fish and Wildlife Service proposed to list these creatures under the Endangered Species Act.

Monarchs have a classic migration from northern latitudes to overwintering southern latitudes that takes several generations to complete. Their affiliation for milkweed plants as both nectar sources and host plants for caterpillars, is a reason to promote growing or protecting milkweed patches.

Watching a western tiger swallowtail, named for its tiger-like stripes and forked tails, l float through a mountain meadow is a fun experience. These large butterflies float on long wings, dipping and fluttering with the wind. Their long wing projections or tails are intended to distract predators which might strike the tails but miss the body. These butterflies nectar on a variety of wildflowers from columbines, to milkweed, to monkshood. A close relative, the anise swallowtail also inhabits southern Utah. These butterflies have heavy concentrations of black along their wing margins and lack the black streaking of the tiger swallowtails.

One challenging group of butterflies to view are the small blues that like to “puddle” – sipping salts and minerals from wet spots on the ground. These ½-1” wide butterflies are mostly blue above, with various spotting or marks on the undersides of the wings. Artic blue, greenish blue, western pygmy-blue, and others require some good looks and photos of both the top and undersides of the wings to aid in identification. Even then, it may be too challenging to make an identification to the species level.

Several late summer wildflowers and shrubs provide abundant nectar sources for butterflies to feed on, including rabbitbrush, asters, thistles, sagebrush, yarrow, and other flowering plants, while others feed on tree sap.

So, if you take photographs of these amazing creatures, upload them to the free sites such as iNaturalist or BAMONA. Even if the species is unknown, community members contribute identifications. It’s a great way to learn the butterflies and to help expand the knowledge of these graceful creatures, one flutter at a time.