Tips to Avoid Centipedes in Hawaii

Bugs scare me. I know it’s an irrational fear, and many of them are harmless, like the roach, giant moth, lizard (yes, I lump lizards in this category), and even the diminutive silverfish, but I just freak out when I see them. I can’t help it.

Bugs are creepy enough, but when they can bite or sting, that’s a whole ‘nother can of worms (I don’t like worms, either). My fear of those bugs is plenty rational. And among the many we normally encounter in Hawaii, there aren’t many biting or stinging bugs more menacing than the centipede. 

Knock on wood, I’ve never been bitten by a centipede, but according to some of my friends who have, it’s no party.

Lisa:  I've been bitten by centipedes three times in my lifetime. The worst (by far) was the bite to my right eyelid. The other bites to my forearm and forehead weren’t too excruciating, merely five or six on a scale of one to ten. The one on my eyelid, well, that one was an eleven. My right eye was swollen shut with tears streaming down from only that eye. My eyelid was so swollen that the skin was a stark white and the surface was stretched to the point that it was shiny.

Kathryn:  I've been bitten many times. They crawl into bed with me then bite me on the back or on my toes. I can be sitting there minding my own business watching TV and a centipede will crawl across my area rug to bite my toes! I have found that if you rub the bite constantly for about 15 minutes, you will dissipate the venom and you won't have any pain. If you leave the bite alone, the concentrated venom will hurt for days! Rub! Rub! Rub! 

Sean:  Top of my left foot when its head got pinched by my slipper, right hand, right forearm, and left eyebrow while sleeping. All very painful and the one on my eyebrow induced a terrible migraine. 

My friends have convinced me – I never want to be bitten by a centipede, ever. But I believe the more we understand centipedes, the better we can avoid them. “Know thy enemy” and all that, right? And to supplement my own research into this crawly arthropod, I was lucky to tap two resources from different perspectives of the insect world – pest control and entomology.

Centipedes in Hawaii

There are about 25 different centipede species in Hawaii. If you’ve seen one, it was probably Scolopendra subspinipes, also called the “Large Centipede” or “Vietnamese Centipede.” Adults are reddish-brown and can be 6 to 9 inches long, with a pair of legs on each body segment. Centipede in Latin means “100-legged,” but they only have 22 pairs of legs.

Centipedes eat other insects, like roaches, spiders, and even other centipedes. And they like to hang out in moist, wet areas outdoors, under bushes or dead leaves.

Some people mistake millipedes for centipedes. Millipedes have tubular bodies and their legs don’t stick out to the sides like centipedes. Millipedes are vegetarian, feeding on organic matter like dead leaves. Although they don’t bite or sting, millipedes do spray a defensive toxin when threatened, so it’s best to leave them alone.

The centipede’s ‘bite’

Near the centipede’s mouth is a set of pincer-like appendages that have poison glands. Justin Duny, owner of Absolute Termite & Pest Control, said, “The centipedes leave two marks on you because they have the pincers. [The amount of pain you feel] I think has to do with the amount of venom that they have stocked in them. Some of it has to do with the actual bite, if they gave you a good one or not. Typically, centipedes aren’t gonna bite you because they want to; they’re gonna bite you because they’re in fear of their life. I think that has a lot to do with how much venom is going to come out.” 

(At left:  a closeup of a centipede's pincers. Photo courtesy of Dr. Steven Lee Montgomery.)

Duny agrees that because of the centipede’s bite, the insect is among his customers’ top concerns. He said, “I would say that’s the thing that people are the most scared of. I’m sure some people could have an allergic reaction, especially in small children or older folks. For a lot of people that have newborn babies, centipedes are one of their main concerns.”

Although Duny has been bitten by a centipede, he admits that it wasn’t too bad for him. He added, “I’m around bees a lot, so I think I have an immunity.” But for most people, he said, “Yeah, the bite is pretty painful. You probably are going to want to call in sick to work. I think you’ll probably have some swelling and it can bruise pretty bad.”

Treatment of centipede bites may include ice packs for the swelling, pain killers like ibuprofen or acetaminophen, and immersing the bite in hot water. If an allergic reaction like difficulty breathing occurs, see a doctor immediately.

Why do they enter my house?

Generally, there are three reasons you might spot a centipede in your home. Duny said centipedes often go looking for moisture during a dry season. He explained, “They need water. They actually have a bad hydration problem and dehydrate really easily.”

On the other hand, heavy rains may drive them into your home to escape flooding. Duny added, “Moist conditions are when centipedes are reproducing, too.”

They may also be looking for food, which is another reason to keep your house as free of roaches and spiders as possible. 

How to prevent centipedes from entering your house

Centipedes will enter through your home’s cracks and crevices. Duny explained, “Every house is built differently, especially in Hawaii with all the additions. Houses are shifting over time, and the shifting creates cracks. There are a lot of double walls that you can’t see. Wood siding doesn’t always fit right up against the house either.”

So the most important thing you can do to prevent centipedes from entering your home is to seal up any cracks and crevices. You can try to do it yourself, or get a professional to do it.

(At right:  centipede specimens from the Bishop Museum's insect collection)

Another measure you might try is diatomaceous earth, which is a fine powder made up of fossilized remains of aquatic organisms. It causes insects to dry out and die when they come into contact with the powder. Diatomaceous earth is sold in gardening stores and works best in dry conditions.

Centipede myths

As often happens with things we fear, myths can sometimes pop up about them, which make them even scarier. So I wanted to see if we can set straight some centipede myths right here. I contacted a local entomologist, Dr. Steven Lee Montgomery, to help me do this. Dr. Montgomery has provided “bug wrangling” for television and movie productions that are filmed in Hawaii, like the movie Tropic Thunder and the TV series LOST.  

Myth No. 1:  Do the smaller, bluish centipedes (baby centipedes) give a more painful bite?

Dr. Montgomery:  “I read of no evidence of this. These quite young, two-inch, bluish Scolopendra were no more or less painful than six-inch biters for me. Both were extremely painful!”

Myth No. 2:  Is it true that centipedes run in pairs, so if you kill one, another could be nearby?

Dr. Montgomery:  “I find no evidence of pair bonding or social behavior, except for maternal care of eggs and fresh hatchlings. It is more likely people are seeing nest mates from a freshly disbanded clutch of hatchlings.” 

Myth No. 3:  When a centipede is killed, does it release a scent that attracts other centipedes?

Dr. Montgomery:  “A freshly dead centipede can attract many predators and scavengers, like other centipedes.”

Well, I still have a healthy fear of centipedes and their bite, but at least I understand them a bit more now. If you want to learn more about the types of bugs we have here, especially the ones that sting and bite, visit your local library for the following books, which were written and published in Hawaii:

  • What Bit Me? Identifying Hawaii’s Stinging and Biting Insects and Their Kin
  • What’s Bugging Me? Identifying and Controlling Household Pests in Hawaii