The bright lights over the soccer field drew moths — and moth enthusiasts — to the Smith River Sports Complex on Wednesday for National Moth Night.
The moth night event, sponsored by the Southwestern Piedmont chapter of the Virginia Master Naturalist Program, is in its second year. Master Naturalist Lynn Pritchett, who spearheaded moth night, said that although Master Naturalists try to be well-rounded in their interests, she has developed a special interest in moths and butterflies.
The event began at 7 p.m. with a seminar for Master Naturalists conducted by Pritchett.
Phil McDonald of High Point, N.C. — also known as the “The Moth Man” — was on hand with displays of moths and butterflies he’s collected, along with moth caterpillars that he raises at home.
McDonald said this summer, he mainly is raising polyphemous moth and luna moth caterpillars, both in the silkworm moth family. Polyphemous moths are large brown and pink moths, and luna moths are the large, pale green moths frequently seen locally around back porch lights on summer evenings.
The main event, however, was at the canoe launch on the Smith River. Virginia Museum of Natural History Executive Director Dr. Joe Keiper set up a white sheet on the platform overlooking the river, lit from behind by an ultraviolet light, also known as a black light.
“For insects, ultraviolet would be the brightest wavelength, because they see light differently than we do,” Keiper said. While black light is not harmful to human eyes, which see it only as a purplish glow, to insects, it looks bright, Keiper said.
While the ultraviolet spectrum is bright to insects, other colors are all but invisible. Yellow, orange and red light does not attract insects, Keiper said, which is the reason that many stores sell yellow-tinted “bug lights.”
“They’re meant to put the orange or yellow light on your back porch, because that’s a wavelength that insects don’t see,” he said. “You can still see, but it’s not going to attract waves of moths and beetles and midges and all kinds of things that could be a nuisance.”
Keiper’s ultraviolet light drew not only small moths, but also stoneflies and mayflies from the Smith River.
Keith and Charlotte Hubbard of Boones Mill attended the event with their friend Nathan Seda of Houston, Texas, and their grandson, Kyler Hubbard, 8, of Sacramento, Calif.
Charlotte Hubbard is a master naturalist with its Blue Ridge Foothills and Lakes chapter, but Kyler, she said, “loves bugs more than anyone I know.”
Before long, Kyler had spotted a June bug, drawn in by Keiper’s ultraviolet light.
According to Keiper, scientists believe that there’s a reason that moths travel toward light, and it isn’t because they’re afraid of the dark.
“Nocturnal insects navigate by the moon,” Keiper said. “The moon is in a fixed position for them; sure, it moves across the sky, but slowly. It’s not like you can fly 10 miles in a straight line towards the moon and truly get closer. You’re still going to be infinitely far away.”
When insects attempt to navigate using a bright light source instead of the moon, they quickly arrive at the light source. Because their brains are hard-wired for simple behavior, “it’s not like they can think their way out of it,” Keiper said. “They get into a cycle and get stuck up against the sheet.”
This is the leading theory, Keiper said, “but no one really knows, and that’s the great thing about science. There’s still so much left to learn.”
For more information on the master naturalist program, contact Southwestern Piedmont chapter adviser Denny Casey at 634-4184.