How To Get Rid Of Dobsonfly, And Do You Really Need To?

Did you find a large, scary-looking creature flying in or around your house? It might be a dobsonfly. In this article, we talk about how to get rid of dobsonfly and whether you need to do it at all.

If you live near a body of water, there’s a chance that you might find dobsonflies in your home. While these large insects look quite intimidating, they aren’t a threat to humans. 

Still, nobody likes one of the largest insects flying around in the house. The dobsonfly is mostly a nuisance pest, although the females are capable of delivering bites powerful enough to draw blood. 

If you’re here reading this article, you’re probably trying to find out how to get rid of these massive bugs.

How Did I Get Dobsonflies?

Dobsonflies ending up in your home were likely drawn to your lights. They are nocturnal creatures, and like many others in the insect world, they find lights irresistible. 

Dobsonflies are mostly aquatic insects, spending the entire larval stage of their lives (three to four years) in the water. 

Their larvae prefer shallow and fast-flowing water bodies, such as small rivers and streams. Full-grown dobsonflies live on land but usually stick close to bodies of water. 

If your house has outdoor lights that you keep on during the night, and you live near a stream of running water like a river, you might find them in and around your house.

They usually don’t like to come inside, but if your window is open just a crack and your lights are on, they might venture inside.

How To Identify Them?

Dobsonflies are easily identifiable thanks to their unusual appearance. The males have one or more inch-long, sickle-shaped mandibles, which give them a menacing look.

The jaws on female dobsonflies are shorter and resemble pincers. The females can bite using these jaws, but the male’s mandibles are not useful in biting.

From the end of the mandibles to the tip of the wings, these bugs can grow up to 5 inches long. Their size and color may vary from one species to another. 

Another noticeable feature of the dobsonfly’s appearance is its wingspan, which can be twice as long as the body. 

The wings are similar to those of a grasshopper’s – two pairs of narrow translucent wings stretching out on either side when spread. 

As for the color, they are usually dull brown or tan. However, some species, such as the Eastern Dobsonfly, can also be bright yellow.

Can They Bite?

Although the mandibles of the adult male dobsonfly are large and scary looking, they are unsuitable for biting. 

They don’t get enough leverage because they are fleshy, and therefore even if they try to bite, it doesn’t do any damage. A bite from a make dobsonfly feels merely like a strong poke or pinch. 

Female dobsonflies can inflict painful bites with their short, sharp, and pincer-like mandibles, powerful enough to pierce the skin. 

However, they aren’t aggressive at all and would bite you only if you handled them roughly. Neither male nor female dobsonflies are venomous or poisonous.

Do They Spread Disease?

Don’t worry; despite their scary appearance, dobsonflies do not spread any diseases. 

Apart from the sharp, stinging pain, a dobsonfly’s bite doesn’t cause any issues either.  However, they might release foul odors in your home if they feel threatened.

How To Get Rid of Them?

Before you take up pest control solutions to eliminate the dobsonflies in your home, consider whether it’s really necessary. 

However, if you’re keen on eliminating the dobsonflies immediately or there are simply too many of them in your home, you may use insecticides.

Leave Them Be

In most cases, they don’t require pest control as they’re just nuisance pests and don’t cause either disease or any other damage. 

As adult dobsonflies live only a few days, it’s just a temporary and short-lived inconvenience.  Moreover, dobsonflies don’t reproduce indoors – they lay their eggs in or around water bodies.

Hence, the best way to deal with dobsonflies is just to leave them be. Pesticidal control isn’t usually recommended. 

Pesticides

However, if you’re keen on eliminating the dobsonflies immediately or there are simply too many of them in your home, you may use the Supreme IT insecticide. 

Create a diluted solution by mixing an ounce of Supreme IT per gallon of water.

Now use a pump sprayer to spray this solution and treat the area around your home’s foundation. 

Remember to cover three feet out from the foundation and three feet up along it. You’ll need a gallon of the solution per Sq.Ft. of area. 

The treated area will need two to four hours to dry, until which you shouldn’t allow people or pets to enter the area.

How To Prevent Them From Coming to Your Home?

Since it’s likely your outdoor lighting that keeps drawing the dobsonflies, consider keeping the lights turned off. You may also replace them with yellow bug-safe lights instead. 

If possible, keep your pool empty during the hatching season so that the bugs don’t lay eggs in it. Most importantly, keep the curtains closed over all your windows at night so that dobsonflies don’t make their way inside.

Frequently Asked Questions

Wrapping up

Hopefully, this article has dispelled any fears you had regarding these large aquatic insects. You may rest assured that dobsonflies won’t harm your pets or damage your garden. 

As mentioned, pest control measures are rarely necessary for these bugs. Thank you for reading, and I hope you can keep the dobsonflies out of your home in the future. 

Reader Emails

Even though they are mostly harmless, their appearance often leads to their downfall.

Over the years, many of our readers have checked in with us about how to get rid of them, and here are some of the methods they have used in their quest.

Letter 1 – Dobsonfly Pupa

 

Frightening larva thing…
Hi!
First, wonderful site. Keep up the good work, and all that. OK, so, the bug: My nephew found it under some rotten wood near Grantsburg, Wisconsin, the other day. My sister saved the little guy from becoming fishing bait, and brought it to me ("Happy Birthday!"). My nephew said that there was what appeared a shed "skin" next to it when he found it, and it was a pale off-white when caught (it’s since turned brownish, as you can see.) It looks dead in the photos, but it is alive, and will squirm around if bothered. It’s legs don’t seem to be usable, however, and remain tucked under it’s body, as do it’s wings. So, do you know what it is? And do you have any ideas of how I can help it survive? Would it be best just to put it under a rotting log, or…? Anyways, thanks a lot.
Will Anderson, MN, USA



Hi Will,
You have a Dobsonfly Pupa. If you think it is scary looking now, just check out the adult males with pincer mandibles by using our brand new site search engine.

Hi… Hah! Oh, no. Thanks. When I showed some friends your site, they pointed out the dobsonflies and said “Jesus, I hope it’s not one of those!” Muahahaha. You wouldn’t happen to have any tips on care, would you? I’ve got it in a little cage now, with moist dirt and some of the wood it was found in. Should I bury it, or do you think out in the open is ok? I had it under a bit of wood, but it was across the cage in the morning. Oh, and it doesn’t need to eat, does it? Thanks again,
Will

Letter 2 – Not a Dobsonfly, but a Fishfly

 

(07/21/2004) Hi,
I hope all is well with you. Last night I saw this big guy hovering around the flood light on the back of my house. I tried to get better pictures, but he moved around pretty fast.
Best Regards,
Ed Cogan



Hi Ed,
Thank you for the photo of a Fishfly, Chauliodes species. These are relatives of Dobsonflies, both belonging to the family Corydalidae. They can be recognized because of their comblike antennae. Larvae are aquatic predators, and it is likely that adults do not feed.

Letter 3 – Dobsonfly visits Gerald Ford Museum!!!!

 

identification
Hello,
We just found this bug on our loading dock. Its total length must be at least 3-4 inches. I think some of our interns were sufficiently freaked out upon first glance. Could you tell me what kind of insect this is (see attached image)? I do not think I have ever come across a bug like this. Any help would be greatly appreciated.
Sincerely,
Jamie
James W. Draper
Registrar
Gerald R. Ford Presidential Museum
Grand Rapids, MI



Hi Jamie,
This is a male Dobsonfly. He is harmless. We had two photos on our homepage at the time you wrote in, including the Bug of the Month for June. We can’t imagine how you missed identifying the Dobsonfly yourself.

Letter 4 – Dobsonfly identified by WTB?

 

Dobson fly
Hi,
Just found your super website and lo and behold – there it was – the gigantic insect I’ve been trying to give a name to! It was a Dobson Fly. Gave us a real shock when my granddaughter brought a dead one over in a large pickle jar that her neighbor found on her back porch. It measured 6 inches from wing ends to tip of pincers! We photographed it with our digital camera and have been trying to identify it ever since. Seems it pinched a lady in the neighborhood. It’s funny that I lived in this area for 60 years and never saw one before. Enclosed is our pic. Keep up the good work!
Barbara Erney
Harrisburg, PA



Hi Barbara,
Happy we could be helpful.

Letter 5 – Portrait of a Dobsonfly

 

Hey, I saw this in my mom’s garden today and I promptly ran in and googled on the expression "what kind of bug is that" – and I ended up at your site and I learned it was a dobsonfly. W00t! Anyway, this fellow was maybe 7" from jaw-tip to wing-tip and the antenna were 6" across. He was spotted in Stowe, Pennsylvania, which is in the south eastern part of the state.
Michael



Hi Michael,
I guess we chose our site’s name wisely. We have always maintained that everyone wants to know “What’s That Bug?” Glad we could be helpful. Your photo is pretty impressive.

Letter 6 – Not a Dobsonfly, but a Fishfly

 

Hi,
I hope all is well with you. Last night I saw this big guy hovering around the flood light on the back of my house. I tried to get better pictures, but he moved around pretty fast.
Best Regards,
Ed Cogan



Hi Ed,
Thank you for the photo of a Fishfly, Chauliodes species. These are relatives of Dobsonflies, both belonging to the family Corydalidae. They can be recognized because of their comblike antennae. Larvae are aquatic predators, and it is likely that adults do not feed.

Letter 7 – Dobsonfly from Peru

 

Peruvian insect
We saw some dozens of flying insects beating against the window of our hotel in Agua Caliente, at the foot of Machu Picchu, Peru. The one attached was no longer working and was about 5cm long. This resembles nothing we know in the UK and I wonder whether you can identify it. Thanks
Peter Seamer



Hi Peter,
This is a male Dobsonfly. Very soon now, in the late spring and early summer, we expect to begin getting Dobsonfly submissions from the eastern U.S. At that time of year, it is one of our most common submissions.

Letter 8 – First Dobsonfly of the Year!!!

 

Bug at work..
This bug was found in a crate at work. It was dead and there was this only one. This is the only picture I got of it, i hope that it helps. thanks
maria



Hi Maria,
Your photo is not the best quality, but it is significant since it is the first photo we have received this year of a Dobsonfly. This is a male. You can tell by his large mandibles. Just yesterday we received a photo of a Hellgrammite, the immature Dobsonfly.

Letter 9 – Dobsonfly larva

 

Pic 4 u
Hi
i LOVE your site, I was looking up the Dobsonfly larva, & noticed you only have one picture,so I thought you might like another one of the larva this one was 4- 5 inches long and about an inch wide, coulden’t belive it was that big, I have more pictures of it’s head,very close up, if you want them oh yeah the reason I e-mailed you was do you have a news letter? if you do I’d Love to get it,I can see why you got the yahoo pick of the week AWSOME SITE!! very well put together, & it’s easy to find what your looking for thanks,
Tina Johnston-Wilson
Goderich Ontario Canada
keep up the great work

Thank you so much Tina,
Your photo is beautiful. We do not have a newsletter. Just keeping the site updated is a handful, though we have toyed with the idea of trying to publish a book. Also thank you for the navigating compliment. I just received another letter from someone complaining she couldn’t find anything on the site. We would love to get the head photos.

Letter 10 – Dobsonfly Gets Screwed

 

Flying Ant Demon! With a Stinger. July 12, 2009 About 2-2 1/2 inches long, 1/2 inch long pinchers. Antennas on head felt like needles. Obviously could fly. 6 legs, stinger on tail size of head. about all i know, my friends uncle put a screw in it because it scared him i think! Ryan Darveaux Arrington, KS

Ryan, This goes way way beyond Unnecessary Carnage.  It actually borders on medieval torture.  This poor male Dobsonfly was perfectly harmless, and now it is dead.

Letter 11 – Dobsonfly Pupa

 

Mysterious larvae? June 6, 2010 Found this creature near my house and wondering what it could be? Notice the wings and pinchers on the head. Jeremy D. Allegan, MI

Hi Jeremy, We just posted a letter and commented on the great number of requests we have received in the last week and a half to identify Dobsonflies and their larvae, called Hellgrammites.  You have submitted a photo of the pupa of a Dobsonfly, and judging by the mandibles, it is a male.

Letter 12 – Dobsonfly from Venezuela

 

Scary looking bug to identify please Location: Puerto Ordaz, Venezuela November 11, 2010 4:26 pm Took the picture on october 29 on a wall right at my job’s door. It was about 1.5 to 2 inches long IIRC. I found it a bit scary because of the (can fly) + (bit painful looking pincers) factors, so I took a pic of it but then forgot about it. Saw it again when checking on old pics on my cell phone so I’m posting it here. Reason I’m asking is because I showed it to my wife and she mentioned it looked like a ”chipo” (Triatoma infestans), that’s considered a dangerous bug here in Venezuela because it transmits the chagas disease, but checking online all mentions of the chipo describes it as a much smaller bug, and with no pincers. Signature: Roberto Etcheverry

Dear Roberto, Though it looks a little different from our North American representatives and it is about half the size, we are confident that this is some species of Dobsonfly in the family Corydalidae.  These are harmless creatures.

Letter 13 – Mystery in the Dirt is a Dobsonfly

 

Molting Creature Haunting My Dreams Location: Upstate New York June 17, 2011 9:48 pm This molting insect was found in my garden (June 16) buried in the soil. I accidentally unearthed it, and I must say that it totally freaked me out! It literally haunted my dream that night. Unfortunately, although I tried to cover it back up, when I revisited it the next day, it had died. I’m just curious about what it could be? It looks like a dragonfly nymph to me, but it was definitely in the dirt. Not sure if this is a good enough picture for identification, but I would rest more easily knowing that it was not actually the creature from the Alien movies! Signature: Molly

Hi Molly, We really wish you had more detail in your photo.  We seem to be getting more requests than usual this morning that we cannot identify.  How large is it?  The mandibles are the only really discernible feature, indicating that this is not a moth.  Sphinx Moths are often found pupating in gardens.  It is not a dragonfly either.  They undergo incomplete metamorphosis.  Though beetles have mandibles, we don’t believe this is a beetle.  Our best guess is that perhaps this is a female Dobsonfly.  See this photo on BugGuide of a female Dobsonfly. Thanks for your reply.  I wish I’d gotten a better picture of the poor guy (gal?).  It was approximately 3 – 3 1/2 inches long – big!  And it may not be clear in the picture, but it had double wings.  The molted skin had two sets of small (1 1/2 cm?) wings, and the new ones appeared larger.  When I found it, it was just under the surface of the soil.  Not sure if that helps. I love your site – thanks for the good work! Molly Hi again Molly, Thanks for the compliment.  All that you have added supports our belief that this is a female Dobsonfly. Hi Daniel, So, guess what?!? I was doing some more gardening this afternoon and found what looks to be another one of these creatures, but at a less mature stage.  I was able to get more photos of it (attached). Definitely a Dobsonfly? Molly

Hi Molly, This is definitely the pupa of a Dobsonfly.

Letter 14 – Pupa of a Dobsonfly

 

Subject: Unknown Bug Location: Alpine Tennessee May 26, 2012 9:21 pm I flipped a rock over on the nettle carrier creek in Alpine Tn. on may 26 of 2012 and found a horrifying bug. I am curious on if this bug is ever been found before or if it is endangered? please help.. Signature: Michael Downs

Hi Michael, This is the pupa of a Dobsonfly, and we receive very few photos from the pupal stage, however, we get numerous identification requests to identify the larva, which is known as the Hellgrammite, as well as even more requests to identify the impressive adult Dobsonfly.

Letter 15 – Dobsonfly Pupa

 

Subject: mystery bug found under rock Location: Ontario July 17, 2013 6:26 pm my friend found this strange thing under a rock on the moon river in Ontario Canada we would really like to know what the heck it is Signature: Scott

Dear Scott, Your friend uncovered the pupa of a Dobsonfly, a large flying insect that is generally found not far from water as the larvae, known as Hellgrammites, are aquatic.  We have responded to many requests to identify Dobsonflies recently.

Letter 16 – Dobsonfly from Peru

 

Subject: Mystery Bug of Peru Location: Aguas Calientes, Peru July 24, 2015 2:33 am This is not the best lit picture in the world but myself and my friend found it at 4am in our hotel room in Aguas Calientes, Peru, before walking up to Machu Picchu. I had heard it flying around our room the night before and thought that a small bird or bat had got in! The bug was about the size of my hand (about 15cm) and we found it on July 11th. I asked my Peruvian tour guide if he knew what it was but he shook his head in terror and swore in Peruvian. It remains a mystery… Signature: Eve

Dear Eve, This South American Dobsonfly has relatives in North America that are also quite large.  Despite his fierce appearance, this male Dobsonfly is perfectly harmless as his mandibles are not designed to bite.

Letter 17 – Dobsonfly from New Zealand

 

Subject: What is this bug?? Location: New Zealand February 8, 2016 2:23 am Sorry, my partner got a little freaked out and the bug got swatted ? Have never seen anything like this before in NZ! Almost like a cross between a fly and a dragon fly! Signature: Kim

Dear Kim, We are feeling sad that the first Dobsonfly image we have received from New Zealand has to be tagged as Unnecessary Carnage.  We found an image on FlickR that is identified as Archichauliodes diversus, and we found another image on Hidden New Zealand Photographaphy where it states:  “New Zealand only has one Dobson fly species, They are also known as toe-bitters, due to their larva having large jaws and their tendency to bite :).”  We suspect the common name of the larva is Toe-Biter, and that is a very commonly used name for the North American Giant Water Bug despite North America having its own species of Dobsonflies.  iNaturalist states:  “Archichauliodes diversus is an insect in the subfamily Corydalinae – the Dobsonflies. In its larval form It is commonly known by the name toe-biter, and its Maori name is puene. The species is native to New Zealand. Although there are other species of Dobsonfly in other parts of the world including Asia, Australia (Archichauliodes guttiferus) and South America, Archichauliodes diversus is the only species of Dobsonfly in New Zealand. The Dobsonfly larva is the largest species of freshwater insect found in fresh water and the only family representatives in New Zealand.”  The site also states:  “The biggest threat to dobsonflies is human intervention,[14] by removing over hanging bush and trees from the waterways. This has a significant negative impact as it is a critical part in the life cycle of the Dobsonfly.[10] The Dobsonfly is only found in good quality water. Any pollution could do serious damage to not only the Dobsonfly but also other species that could be potential food source.”  Csiro has some good information on Australian Dobsonflies.  Though its larva is called a Toe-Biter (or Toe-bitter), they are not considered dangerous to humans.  Adult Dobsonflies might also bite if carelessly handled, but they do not pose any threat to humans.  We hope that should you happen to encounter another individual in the future, you will allow it to survive and that you will provide us with an image of a living Dobsonfly. Hi Daniel, Thank you for that information, I will definitely make sure next time my partner doesn’t get to it first. We live on a golf course so hopefully I will encounter another one and I will definitely take a pic for you ? Kind regards, Kim

Letter 18 – Pupa of a Dobsonfly

 

Subject: What is this?! Location: Tennessee May 17, 2016 12:45 pm Found near a creek. Wriggling around on a rock. What is it? Signature: Raya D Whitworth

Dear Raya, This is the pupa of a Dobsonfly.  We get numerous submissions of images of adult Dobsonflies, and we get a fair number of images of larval Dobsonflies known as Hellgrammites, but images of Dobsonfly pupae are not that common.

Letter 19 – Western Dobsonfly

 

Subject: Flying beatle? Looks like bark. Location: Western Oregon July 7, 2017 6:40 pm My husband found this bug just hanging out on a rag he had set on the back porch by our garage. I’ve googled “flying bug that looks like bark”. Looked at images…etc. I am not a bug expert, it’s hard for me to tell what this is, and I can’t find my insect identifier book. Can you help? Seems it’d be easy for someone with some knowledge. 🙂 Signature: Laura W

Dear Laura, This is really a wonderful image of NOT a Beetle, but rather a Fishfly, which we identified as Neohermes californicus on BugGuide.  Charles Hogue calls this species the Western Dobsonfly.

Letter 20 – Yellow Dobsonfly from India

 

Subject: bug from Andhra Pradesh India Location: Andhra Pradesh, India August 14, 2017 11:25 am Can you identify this bug? I found it outside the Borra Caves in Andhra Pradesh, India. I’ve never seen anything like it before. Signature: Celeste

Dear Celeste, This is really a gorgeous yellow Dobsonfly, and we believe it is the same as this Dobsonfly from Burma that we identified as Nevromus austroindicus.  According to the Aranyaparva blog:  “a dobsonfly Nevromus austroindicus. Very few people have seen this insect. In fact, they gave it a name and formally described it as recently as in 2012! The specimen was from Karnataka. Shyamal has described it as a living fossil in his blog. The males have spectacularly long, tusk-like intimidating mandibles. This is a classic case of how looks can be deceptive. Although these pincers are long, they are weak and help only during the mating season; to fight away other males and to impress the females. The females, like the one we saw, have short, sharp pincers. If we try to mess around with them, we must also brace ourselves to lose some blood”  and  “Very little is known about this Western Ghats species Nevromus austroindicus. The fact that it has been described so late shows the lack of information about it.”  Thanks Daniel!  I do a type of hand embroidery called Stumpwork and bugs are one of the things that I like to make.  And as an added challenge, I like to do ones that I find when we travel. Celeste How wonderful.  Please send us some images if you can.

Letter 21 – Dobsonfly Pupa

 

Subject:  Active dobsonfly pupa Geographic location of the bug:  Wilberforce, Ontario, Canada Date: 07/08/2019 Time: 08:12 PM EDT Your letter to the bugman:  Hi there! I’ve always enjoyed your site, and thought you might enjoy these photos from a video of a dobsonfly pupa in my garden (if you would like the video, I’m happy to share – just email me). I noticed it moving after watering the plants. I’ve never seen the pupal forms before (just larvae and adults most years) and wasn’t sure at first what was going on. But it seems to be re-packing the cell it made in the soil. Once it seemed to be finished, I placed a small bit of birch bark over the hole for a bit more cover. We live near a river in a woodland area, and this year had quite a number of hellgrammites emerge one day in the spring – 20 that we could see! How you want your letter signed:  Erin

Dear Erin, Thanks for sending in your images along with personal observations.  While we don’t contest that this is an immature Dobsonfly, we question perhaps that it might be a pre-pupal Hellgrammite that is preparing for metamorphosis rather than an actual Dobsonfly pupa.