Dismals Canyon - Dismalites

Past twilight the canyon lights up with tiny bioluminescent creatures we call Dismalites. These "glowworms" require a select habitat to survive and are unique to only a few places on Earth. Dismals Canyon is one of only a few places outside New Zealand and Australia where they are known to exist.

Guided night tours are available throughout most of the year.

Flashlight trails from a Dismalite tour:

magnify


	Dismalite Night Tours: Friday and Saturday nights at 8:30 pm Note: Due to later and later sunsets throughout the spring and early summer, the night tours will change to a later time at night. So check back here for the current night tour time before planning your visit.

Colloquially known as Dismalites, they are the larvae stage in the life of an insect called the North American Orfelia fultoni that emits a bright blue-green light to attract food, in the form of other flying insects.

It requires a select habitat to survive: humidity to prevent it from drying out; hanging surfaces to allow it to build sticky webs to trap the food; an adequate food supply of insects; a still atmosphere to prevent lines from tangling and darkness to allow it to show a light.

Dismals Canyon provides the perfect habitat for these unique insects to survive.

When looking up at the moss covered canyon walls it's hard to tell where the Dismalites stop and the stars begin.

magnify

Although the creatures known locally as Dismalites are “close cousins” of rare glowworms found in Australia and New Zealand, they are actually fly larvae, said Auburn University entomologist Gary Mullen, who has studied the insects.

“It’s a very unusual group of flies, very closely related to fungus gnats,” Mullen said. Fungus gnats are found near mold and the glowing insects are thought to be so plentiful in Dismals Canyon because of the abundance of moisture and dark areas.

“The steep, well-shaded rock faces and very humid cave-like setting with a lot of algae offers a place where they can concentrate their numbers,” he said. “It’s an extraordinarily large concentration of flies.”

Although the insects were initially believed to be the only ones in North America, Mullen said since classifying them (they are classified as Orfelia Fultoni; family name, Keroplatidae), he has seen a few others in southern states, just not typically in large groups.

What makes the Dismals population so unusual is the large number of them, he said. On nights when conditions are right the steep rock face looks like a star-filled sky. Best viewing times are May through September, although they are seen in smaller numbers year ’round.

The light comes from a chemical reaction in two pairs of light-producing structures, one in the thorax and one near the tail end, Mullen said.

“The light is produced biologically, similar in principal to what fireflies produce,” he said. “They produce a chemical reaction, mixing compounds to create a steady glowing light or a flash. Most are a steady glow.”

The insects use the light to attract tiny flying insects into a web-like substance.

“They trap them in a sticky substance, strands of mucilage,” Mullen said. “Not really silk but the same idea, like a spider’s web.”

Mullen, whose students raised the larvae to adulthood to determine how to classify them, said it’s unlikely people would see the larvae outside of Dismals Canyon.

“You’d have to look for them very carefully. There’d only be one or a few,” he said. “They go almost completely unnoticed in the wet areas along streams. Unless you’re out there in dead of night, you wouldn’t see them.”

If you plan on taking the Dismalite Night Tour, you will want to bring a flashlight (preferably one with a red filter).

About Red Light and Night Vision:

While taking a Dismalite Night Tour, you may see thousands of Dismalites, but most are very dim and may be hard to see at first. This is due to the human eye's inability to adapt very quickly to the dark.

While taking the night tour, most people (if not all) should have a flashlight in order to see while walking through the canyon. When everyone stops to look at the Dismalites, everyone should turn off their lights. Otherwise, it's hard to see most of the Dismalites.

Although portable illumination is necessary, the white light from a regular flashlight is detrimental to your night vision. Especially if someone points a flashlight in your face (even if for a brief moment).

We recommend using a red filter on your flashlight (or something to mask out most of the light). The use of a red filter (or simply, a red light), enables you to have better night vision when you turn off your light. . . . Keep reading for a better explanation of why we recommend the use of a red filter.

The human eye has two types of sensors — rods and cones. Cones provide the best visual acuity (focus and fine detail), but require good illumination. By contrast, rods are very sensitive at low lighting levels, and hence provide a person's night vision. However the rods which impart night vision take up to 30 minutes to adapt fully to the dark (think about how long it takes for your eyes to adapt when you enter a dimly-lit restaurant or dark theater). Just a brief exposure to a bright light can "bleach out" the rods and wipe out a person's night vision for many minutes. Rods are insensitive to red light though. So by using a red filter on your flashlight, you can provide enough illumination to be able to walk through the canyon during the tour without compromising your (or anyone else's) night vision.