Bow Bugs: How to Know You Have Them and What to Do If You Find Them

By Karen Peterson | From the May-June 2022 issue of Strings magazine

“What happened to my bow?” read the title on a Reddit post. Beneath the plea was the image of a bow, its hair dangling from the tip like a long, thin ponytail. The answers came almost instantaneously, the verdict unanimous: the cause was most likely the work of the dreaded bow bug, what entomologists call dermestids from the Dermestidae family of beetles.

Bows for violins and other members of the family are not the only instruments affected. Bow bugs have been found in clarinets, flutes, even saxophones. But bows appear to be the voracious beetle’s most sought-after meal.

“One in five [customers] who come in for a bow repair have bow bugs.”

There are nearly 30,000 species of beetle in the United States alone. Whether bow bugs are, as some suggest, a member of the “carpet beetle” clan or, as others claim, “the museum beetle” (Anthrenus musaeorum), they’re both from the same group of “skin” beetles. In fact, the root of the word dermestid is Greek for “skin eaters,” which is kind of what these bow-snacking arthropods do for forensic laboratories, zoological museums, and taxidermists: provide a natural, fast, and efficient way of cleaning skeletons. 

No matter what you call them or the services they are qualified to perform, bow bugs live, breed, and feed in your violin case. It is the fuzzy larvae, not the mature bugs, that really dig in. The target is the horsehair on the bow—or, specifically, the keratin protein within the horsehair. The case is an environment made to order, dark and cozy and most often, when playing host to bow bugs, stored unopen for long periods of time.

“They’re just like any creature,” says Daniel Medina, a bow restoration specialist at Johnson String Instrument in Newton Upper Falls, Massachusetts. “They try to find a place to lay their eggs where there’s food and shelter, so their offspring will thrive.”

Medina, a violist, has had a case of bow bugs in the past, so he knows how customers feel when they walk in distressed about finding bugs and shredded bow hair in their violin case. “What most people see are molted shells, which are beige in color, in their instrument case,” Medina says, for clarification.

Although Medina admits that it might be an exaggeration, he estimates that “one in five [customers] who come in for a bow repair have bow bugs.” The shop repairs 1,500 to 2,000 bows a year. Whatever the true percentage, “a lot of people have bow bugs,” he says.

No one likes to hear about an infestation, let alone one that has a direct impact on an instrument they handle and play. Oftentimes, customers “don’t believe me,” says Medina. To set the record straight, Medina created an informational handout, titled “Bow Bugs: I Did Not Just Make Them Up.” His sage advice includes the following:

For players who wonder whether the damage to their bow was caused by bow bugs: “Usually, bow bugs find their way into cases that have been in storage. If you open your case and find broken hairs with jagged ends, they were probably eaten by a bow bug. Sometimes unlucky bows can have hairs eaten even if stored for just a couple days.” 

Fortunately, this is a problem restricted to the bow. “Your instrument is safe,” says Medina’s handout. “Bow bugs eat protein, which includes hair, unwound gut strings, genuine whalebone wraps, tortoise shell frogs, or horn frogs. Violins are made of wood and most varnishes are safe.”

As for where these little pests come from: “They live in many homes, often hiding in walls, under floorboards and carpets, and other overlooked places. Even the cleanest of homes may have bow bugs.”

At Ifshin Violins in El Cerrito, California, general manager Felicity McCarthy also reports a steady stream of customers with bow-bug problems. She also has noticed an “unexpected” uptick in bug cases over the past two years. McCarthy points to the pandemic.

“I think people were bored and going into their closets and pulling out an old violin, thinking that they could start playing it again,” says McCarthy. “If you’re a professional and playing your violin all the time, you won’t see them.”

“Play your violin” is McCarthy’s number one mantra for keeping bow bugs at bay. After that gentle admonition, she joins Medina in a “practical” overview of how to handle the “small and voracious” pests, as McCarthy describes them.

How to avoid and get rid of bow bugs:

1. If you know or think it’s likely that you have bow bugs, remove the bow and the violin, then give the case a “vigorous” cleaning, using a hand vacuum and making sure you get into all the creases and crevices, says McCarthy. “Then leave the case open in the sunlight,” she advises. Bugs that like the dark don’t fare well in the light. “It’s not necessary, but you can also swab down the case with isopropyl alcohol.”
2. In most cases, it’s a good idea to get your bow rehaired—unless you plan to put the case back in storage. Once the case is carefully cleaned, the odds are good that the bugs won’t return. There are, of course, exceptions. McCarthy calls it “Murphy’s Law of Bow Bugs.” But just because your case has been in storage doesn’t mean you should expect to find evidence of bow bugs. “I’ve seen decrepit bows with old hair untouched by bugs,” she says. 
3. In terms of prevention, or to be absolutely sure not one bug is left, there are solutions. One is natural: Place lavender sachets, moth-repelling cedar balls, or camphor wood blocks in the case. “They don’t necessarily kill the bugs,” says McCarthy, “but bugs tend to avoid the smell.” 

While Johnson String Instrument sells lavender sachets, Medina also recommends using an insecticidal spray repellant after carefully vacuuming the case. For best results, use a repellant that includes permanone or permethrin as an ingredient, he says. But a word of warning: Medina says that permethrin can be harmful to cats, especially those who like to cozy up in a violin case. 

Most important, never use old-fashioned chemical moth balls. Inhaling the fumes is hazardous to your health.