European hornets are large insects, measuring 3/4 to 1 3/8 inches long. Although they are not naturally aggressive, they have the potential to sting if they feel threatened. These hornets feed on various insects, including yellowjackets, butterflies, and bees source.
As a woodland species, European hornets prefer natural cavities such as tree hollows for constructing their nests. These insects typically don’t cause problems in natural areas, but they may take up residence in barns, sheds, or attics in some cases source. Foraging European hornets pose little hazard to people unless they are provoked source.
European Hornet Overview
The European hornet, or Vespa crabro, is a large insect, typically measuring between 3/4 to 1 3/8 inches long. It has a brown body with yellow stripes on its abdomen and a light-colored face. Their black and yellow-banded abdomens also have V-shaped markings.
- European hornets build fragile, tan paper nests
- Nests are usually found in concealed places
- Examples include hollow trees, barns, outbuildings, hollow walls of houses, attics, and abandoned bee hives
Source: University of Maryland Extension
European hornets are native to Europe and Asia. They were first introduced to North America from central Europe and were detected in the 1840s. Since then, they have spread to most of the eastern United States, reaching as far west as Louisiana and the Dakotas.
Source: Penn State Extension
Behavior and Adaptations
European hornets are predators that primarily hunt at night, making them somewhat nocturnal. They have a diverse diet which includes:
- Bees: European hornets often prey on honey bees.
- Flies: They also feed on other flying insects like flies.
- Wasps: Smaller wasp species like yellow jackets can become their prey.
The European hornet is a eusocial wasp that belongs to the Vespidae family. Their colonies include a:
- Queen: The reproducing female who lays eggs.
- Workers: Sterile female offspring who help care for the brood and maintain the nest.
- Drones: Male hornets that mate with the queen, dying soon after mating.
European hornets build fragile yet characteristic nests, typically in concealed locations like:
- Hollow trees
- Hollow walls of houses
- Abandoned bee hives
The nests are made of tan paper constructed from chewed wood fibers mixed with saliva, forming hexagonal cells in which the queen lays her eggs.
Only mated queens survive the winter in sheltered locations, such as under tree bark or in crevices. In the spring, each queen starts a new nest without reusing old ones. The survival of queens during winter ensures the continuation of the species the following year.
The European hornet is a fascinating and important predator in its ecosystem. As a nocturnal hunter, the hornet preys on many other insects, playing a key role in maintaining a balance among species. With specific nesting habits and a social structure that ensures their survival, European hornets have adapted well to their environment.
Stinging and Risks
Sting Frequency and Aggressiveness
European hornets are a type of social wasp. While not naturally aggressive towards humans, they might sting if they feel threatened. Some factors that could trigger a sting include:
- Swatting at the hornet
- Disturbing their nest
- Sweat or strong scents on your body
Comparing European hornets to other stinging insects:
|Low (single sting)
Sting Effects and Treatment
A European hornet sting can cause localized swelling and pain. To treat a sting:
- Remove stinger, if present (only honeybees leave a stinger)
- Clean the area with soap and water
- Apply a cold pack for 15-20 minutes
Over-the-counter pain relief medication like ibuprofen can help in managing the pain.
In some people, European hornet stings could trigger an allergic response, leading to symptoms such as:
- Trouble breathing
In case of an allergic reaction, promptly seek medical help. Some individuals might need an Epi-pen or other medical treatment to counter the effects of the sting.
Prevention and Control
Protecting Your Home
To prevent European hornets from entering your home, ensure that all entry points are sealed. For example:
- Seal gaps around windows and doors.
- Install window screens.
- Close up wall voids and other openings.
Additionally, limit hornet attraction by following these practices:
- Don’t leave food outdoors and cover trash bins.
- Turn off porch lights at night as they attract insects.
Safely Removing Nests
European hornets build fragile, tan paper nests in concealed places such as hollow trees, barns, attics, and abandoned bee hives. If you discover a nest:
- Wear protective gear, such as gloves and goggles.
- Keep a safe distance and don’t disturb the nest.
- Use a hose to spray water and dislodge the nest, if it’s accessible.
- Repeat the process until the nest is removed.
Remember, do not attempt to remove large or inaccessible nests on your own.
Pros of this method:
- No chemicals involved.
Cons of this method:
- Can be dangerous for inexperienced individuals.
When to Involve a Pest Control Professional
Certain circumstances require the expertise of a pest control professional:
- If nests are located in hard-to-reach places or pose a threat to your family.
- If hornets have entered your home and established a nest in wall voids or attics.
- In case of large infestations or multiple nests.
Professionals have access to specialized equipment, materials, and knowledge required to tackle European hornet issues effectively and safely.
Comparison of Do-It-Yourself (DIY) vs. Pest Control Professional:
|Pest Control Professional
Remember, as European hornets are a social wasp species, it’s essential to handle them with caution. Don’t take unnecessary risks, and seek professional help when required.
Over the years, our website, whatsthatbug.com has received hundreds of letters and some interesting images asking us about these insects. Scroll down to have a look at some of them.
Letter 1 – European Hornet attracted to Porch Light
Subject: Huge wasp out at night! What is it?
Geographic location of the bug: Northeastern Pennsylvania
Time: 10:50 PM EDT
Hello, For the last two months or so we have been seeing one or two of these massive wasps out at night, hanging around our porch light. Once or twice one has come at me when I am in the back yard with the flashlight. They are at least 1.5 inches long.
I can’t figure out what it is because all of my searches yield people insisting they are giant Asian hornets, which they obviously are not. Can you ID this? Do you know why it is active at night? (My guess is they are hunting the bugs around our porch light, but is that normal?) Are they aggressive?
How you want your letter signed: Laura Recene
Letter 2 – European Hornet Kills Dragonfly
Cicada Killer Carnage!
Location: Milton, DE
August 7, 2011 9:34 pm
Hello again Bugman!!
On our recent vacation to Delaware, we also were lucky enough to catch this awesome bug on bug carnage, which we think is a Cicada Killer making a meal of a dragon fly. We also took some video of it since my boyfriend thinks these bugs are absolutely awesome. Poor dragonfly had his head ripped clean off!
We were wondering why it went after a dragonfly, however. Perhaps the coloring being close to that of the cicada made it confused? Or do they regularly snack on other bugs?
Signature: Bruce and Ren
Dear Bruce and Ren,
You have mistaken a European Hornet, Vespa crabro, for a Cicada Killer, which explains why the prey in your Food Chain images is not a Cicada. According to BugGuide, they are: “Predatory on other insects, used to feed young. Also girdle twigs to drink sap.” We cannot explain why the Dragonfly was killed and decapitated, and then abandoned. Insects are not prone to killing for the sake of killing. They either defend themselves or kill to eat or to provide food for their offspring. We wonder why the European Hornet killed and decapitated the Dragonfly and then abandoned it. Possibly it was disturbed by the camera. Perhaps one of our readers will have the time to identify the species of dragonfly.
After browsing your site for a bit we started to suspect our bug may have been a hornet when we saw the coloring wasn’t quite right for a cicada killer. We’re glad to have our suspicions confirmed. We were surprised, though, as the hornet was flying around us while we were throwing a frisbee, and did not seem in the slightest aggressive, even when we got close to take pictures (and we were close enough to hear the crunching! Yuck!). Still an awesome sight we were glad to stumble upon. I forgot to mention, that particular bug was seen at the Prime Hook Wildlife Reserve in Milton, DE. Great place to visit. Thanks again for your help!
Bruce and Ren
Letter 3 – European Hornet
Subject: Giant wasp in NJ
Location: New Jersey
May 13, 2016 5:09 pm
I pump gas in Northern New Jersey, and i found this big guy behind a gas door. I ended up removing the gas cap and filling the car before i even noticed, and was too afraid to put the cap back on.
I managed to snap the fist photo while in was still on the gas cap.
I was able to get it out with a broom without killing it, and snapped a second photo. I brought it to a safe distance and set it free.
It was a out an inch to an inch and a half long, yellow and black patterned abdomen, with black and blood red spattered on the head and back
Can you help me identify this type of bee/ wasp thing?
Signature: Sincerily, cstar4004
This is an introduced European Hornet, Vespa crabro, a species that has been established in North America since the end of the 19th Century.
Letter 4 – European Hornet
Subject: Huge hornet
Location: Blythewood, SC
July 21, 2017 8:19 pm
We live in Blythewood, SC and tonight this hornet came on our deck and then 4-5 others after it was killed. I need to know what kind of hornet as I have small children and am now terrified to let them go outside.
Signature: Jessica Brasy
Letter 5 – European Hornet attacted to light
Weird looking demon wasp bug
September 28, 2009
I saw this bug crawling outside my window tonight and I’ve never seen anything like it here! It looks like a cross between a mutated yellow jacket and a wasp. I checked your site but the closest thing I think could be is some kind of cicada killer but I’m not sure. The pictures don’t really give you a sense of size but I’d say the bug is about 3 inches long and the abdomen is about half and inch wide. Sorry about the pictures, it was flying quickly in and out of sight and those were the best pictures I could catch of it.
Thanks for your time and I love the site!
We have been getting numerous reports of European Hornets, Vespa crabro, this year. This introduced species is very adaptable, and it may displace native species once it becomes established in an area.
Letter 6 – European Hornet eats Swamp Darner
Large redand yellow bee/wasp?
September 2, 2009
Would like to know the name of this bee-like bug that I found eating a dragonfly
The predator in your photo is a European Hornet, Vespa crabo, an introduced species, so we are tagging it as an Invasive Exotic. You can read about the species on BugGuide. The prey seems to resemble one of the Pilot Darners in the genus Coryphaeschna, but we are uncertain if the range is a far north as Maryland. We would love assistance with the Dragonfly ID. We didn’t have much luck on this Dragonfly of Maryland page.
Letter 7 – European Hornet found in Car!!!
Subject: European Hornet, I think
Location: Bucks County, PA (In my car!)
May 13, 2014 7:34 pm
Hi there bug man!
Today I found this huge bug in my car. It couldn’t make it’s way out and people in the parking lot were gathered round with various solutions. Unfortunatly, it finally balled up and died. It looks like it was nesting in the door of my car. I’ve sent pictures and video. Sorry for the comentary but it freaked me out. Never saw one before! Could you tell me if I have identified this bug correctly? Thanks so much!
Signature: Judy “freaked-out” Sawyer
We agree that this is a European Hornet, Vespa crabro, but we do not believe it was attempting to nest in your car.
Letter 8 – European Hornet Kills Dragonfly
Subject: European Hornet eating Dragonfly
Location: Westfield, NJ, USA
July 16, 2012 10:58 am
My own internet research led me from my initial suspicion of ”Cicada Killer” to a more accurate labeling of ”European Hornet.” I pulled into my driveway in Westfield, NJ, got out of the car, and heard a strange buzzing/flapping noise. The dragonfly was on its back, struggling, with the hornet clinging to its thorax. By the time I got batteries in the camera, the battle was over, and the hornet was butchering its catch, presumably taking pieces back to the hive.
I have more photos, and even videos of the carnage! If you’re interested, check out http://www.flickr.com/photos/53449201@N06/sets/72157630604296946/
This was an amazing event. I had to leave before the hornet was done with its work, and when I returned home an hour later, all that remained was all four wings of the dragonfly, attached to a tiny piece of thorax exoskeleton! I saved them in a tupperware.
This is not the first time we have received documentation of a European Hornet preying upon a Dragonfly. Since the European Hornet is an introduced species and since we doubt there are many natural predators of Dragonflies in the insect world, the cumulative effects of such predation might have negative ramifications on our local Dragonfly populations. Thanks for your excellent description of the events.
Letter 9 – European Hornet Nest
Subject: European hornet ?
Geographic location of the bug: north Georgia
Time: 06:13 PM EDT
Your letter to the bugman : Found this hornets’ nest at the base of a tree in north Georgia. The guards at the entrance were all fanning the nest. I think this is the European hornet but would like confirmation. Sorry the photos are blurry – actually they are freeze frames from a long video clip. FWIW I am a Patreon donor to WTB!
How you want your letter signed: Bruce Carlson
Thanks for your patronage. We apologize for the delay, but Daniel is currently in Ohio for Mother’s Day and the internet here is woefully slow. These are definitely European Hornets. At first we were not convinced this is a nest because European Hornets and many other Wasps will feed on sap that is oozing from trees. According to BugGuide: “Paper nest is built in hollow trees, or in human structures such as attics” so we also concur that this is a nest.