Are Burying Beetles Poisonous? Debunking the Myths

A burying beetle

Interestingly, some burying beetles possess antibacterial secretions that help protect their offspring from infection. These secretions are not harmful to humans and can even be beneficial in some cases.

For example, Nicrophorus vespilloides, a European species of burying beetle, uses antimicrobial secretions to sanitize carcasses for their developing larvae, ultimately reducing the spread of harmful bacteria. 

Identification and Characteristics

Physical Appearance

They typically display black coloration with bright orange or red markings on their elytra (hardened forewings), and sometimes on their head, face, or tips of their antennae.

The American burying beetle (Nicrophorus americanus) is the largest carrion beetle in North America, ranging from 1.0 to 1.8 inches (25 to 35 centimeters) in length.

They are also known as the giant carrion beetle.

A close relative, the Tomentose burying beetle is also find in part of America and Canada.

Range and Distribution

American burying beetles were once widespread throughout North America, but their populations have since declined, leading to their classification as an endangered species.

Their ability to tolerate warmer temperatures is limited, making them vulnerable to climate change.

Habitat and Behavior

Burying beetles are nocturnal creatures, typically burying carcasses during the daytime for reproduction. They secrete substances to slow the decomposition process of carcasses for their maggots to consume later.

Key features:

• Brightly patterned
• Clubbed antennae
• Endangered species
• Nocturnal

Life Cycle and Reproduction

Breeding and Mating

Burying beetles, active insects usually during the night, engage in a unique mating process. They often locate a small bird carcass, which serves as a breeding site.

Parental Care

These insects display a high level of parental care:

• Both male and female beetles tend to their offspring.
• They defend their brood from predators like ants or mites.

Development of Larvae and Eggs

The lifecycle of burying beetles includes the following stages:

1. Eggs: Laid in the soil nearby the carcass.
2. Larvae: Hatch and move toward the carcass for nourishment.

Comparative table of Egg and Larvae development:

Ecological Importance

Scavenging and Decomposition

Burying beetles are significant members of the ecosystem due to their scavenging abilities. Their role involves:

• Locating dead animals for food
• Burying carcasses underground

This process aids decomposition and supports the recycling of nutrients in the environment.

Carrion Consumption

As the largest carrion beetle in North America, the American burying beetle specializes in consuming dead animal matter. They:

• Can reach 1.0 to 1.8 inches in length
• Use clubbed antennae to detect food

This allows them to locate and consume small dead animals, which helps to keep ecosystems clean and prevent the proliferation of bacteria.

Benefits to Ecosystems

Burying beetles provide considerable advantages to the ecosystems they inhabit:

• Promote rapid decomposition
• Control pest populations
• Act as pollinators

Endangered Status and Conservation Efforts

American Burying Beetle

The American Burying Beetle (Nicrophorus americanus) is a threatened species, having been reclassified from endangered to threatened under the Endangered Species Act in 2020 by the U.S. Fish and Wildlife Service.

Originally found in 32 states, this unique insect now only inhabits two.

Threats and Challenges

The decline in the American Burying Beetle population is attributed to various factors:

• Habitat loss: Increased urbanization and land development have led to the destruction and fragmentation of their natural habitats.
• Climate change: Shifting climate conditions can negatively impact their food sources and create unfavorable environments.
• Competition: Invasive species and other beetles can compete for resources, making it difficult for the American Burying Beetle to thrive.

Conservation Strategies

Several conservation strategies have been implemented to protect and recover the American Burying Beetle population:

• Reintroduction efforts: Captive breeding and reintroduction programs are essential for increasing population numbers.
• Habitat protection: Preserving and improving their habitats can ensure a suitable environment for their survival and growth.
• Research and monitoring: Continued research is needed for better understanding and monitoring of the American Burying Beetle and its habitat requirements.
• Collaboration: Cooperation between state and federal agencies, non-government organizations, and private landowners facilitate endangered species protection.

Interaction with Humans

Are Burying Beetles Poisonous?

Burying beetles are not considered poisonous or harmful to humans. They can bite, but these bites are usually not dangerous to people.

Burying beetles are important scavengers in the ecosystem, feeding on small dead animals like rodents and helping decompose their bodies.

Burying beetles have the potential to transmit diseases to humans indirectly through contact with dead animals they have handled. However, no specific cases relating to burying beetles are documented.

In general, humans should avoid direct contact with dead insects and animals to prevent diseases related to zoonotic pathogens, which are microorganisms that can spread between animals and people.

The CDC discusses zoonotic diseases and the importance of avoiding direct interaction with dead animals.

Prevention and Control Measures

If burying beetles become a concern in certain areas, like Block Island, where the endangered American burying beetle (Nicrophorus americanus) can be found, some control measures can be implemented:

• Avoid leaving small dead animals in open areas.
• Practice proper disposal of rodent carcasses.
• Use traps and baits if necessary, targeting specific rodent populations.

Although burying beetles do not directly harm humans, it is essential to maintain a balanced ecosystem and preserve endangered species like the American burying beetle.

Researchers from various institutions, continue to study their behavior and ecology to better understand their role in nature and develop effective conservation strategies.

Pros and Cons of Burying Beetles in the Human Environment

Burying Beetle

Dear MsRobin,
This is indeed a Burying Beetle in the genus Nicrophorus.   The Banded Sexton Beetle, Nicrophorus investigator, which is pictured on BugGuide, is a strong possibility for species identification. 

The dead voles you have found in your yard are likely a contributing factor in observing more Burying Beetles this year.  The mystery would be “What is causing the voles to die?”

Letter 3 – Black Burying Beetle

Swimming beetle saved from a tragic end? And a beautiful orange/yellow caterpillar.
Hi again Bugman!
After perusing your wonderful website some more, I had to ask you about two more bug pictures I have. The first is of a beetle we found in the sand at low tide on the Oregon coast.

The tide was coming in and he was about to get swept away, so I picked him up on a shell and carried him to safety. I appreciate you encouraging people not to kill the bugs they find; I have a cup dedicated to catching my house spiders so I can put them outside (if I can get to them before my cat does).

The second picture is of a gorgeous caterpillar we spotted on a path at a beautiful spot on the Oregon coast called Beard’s Hollow. The path to the coast there is so beautiful, and simply covered with beautiful bugs of all kinds!

I’m also sending a picture of a slug with pine needles stuck to its butt because I think it’s funny. I don’t even know if a slug is an insect… but figure you may appreciate it anyway! I know you all are busy; any help will be much appreciated!

Thank you!
Sarah D. from Washington State

Hi Sarah,
This is a Black Burying Beetle, Nicrophorus nigrita. We will attempt to identify your caterpillar as well.

Letter 4 – American Burying Beetle

biggest beetle iv ever seen
this flying beetle thinggie was spotted and photographed inside of a crushed dishwasher in the metal pile at the dump on Nantucket island in August 05.. it was at least three inches long i only got one shot of it before it flew off.. what was it?
August

Hi August,
This is an American Burying Beetle, Nicrophorus americanus, and our beetle guide says they grow to 35 mm, or just about 1 1/2 inches, which is still pretty large. I guess you found it in the dump as that is probably a good place to find carrion, the larval food source.

It is often attracted to lights and is found near dead animals.

Ed. Note: This just is from Eric Eaton. (09/12/2005)
“If that image is indeed an American burying beetle, and it sure does look like it, then you have a “scoop.” The American burying beetle is a federally listed endangered species.

It is critical that we identify EXACTLY where this specimen was photographed. It may represent a new record, and/or reflect a successful reintroduction effort.

The locality information, and the image, should be forwarded to someone at the U.S. Fish and Wildlife Service. Please keep me posted on this most important find. Thanks. Eric”

(09/14/2005) Followup from Eric Eaton:
A quick Google search turned up that they do have a release site on Nantucket Island for the American burying beetle. I found a couple of people to e-mail to, so maybe we’ll find out more at some point.

Looks like they need to do a bit more public awareness so folks know about the insect! Eric

Letter 5 – Black Burying Beetle

My friend Joseph and I found this bug while chatting on the photo drive at the Art Center College of Design in Pasadena, CA. At first, I thought it was a stinker bug and Joseph tried to squish it to see if it would really stink, but in a lightning-quick move.

I stopped him just before his foot hit the ground. Upon a second and closer inspection, I found out it was not a stinker bug. Since we are photo and film students, we decided that we needed to have a picture taken of it, so we did.

Now I am sending it to you for your website.
Thanks a bunch.
Bettina

Hi Bettina,
I am so happy to hear you and Joseph are having fun while pursuing your studies. As I told you in front of my class, this is one of the Burying Beetles. Further research on BugGuide leads me to believe it is Nicrophorus nigrita, the Black Burying Beetle.

Burying Beetles often work as a pair when they locate a small dead animal like a mouse or bird. The beetles dig a pit under the corpse until it is below the surface. Then they bury the critter and lay eggs.

I also noticed some mites on your beetle when you presented it to me in that American Spirit cigarette pack. The mites hitch a ride on the beetle and feed on maggots that are attracted to the rotting flesh.

Letter 6 – Artist’s Rendition of a Sexton Beetle

Big Flying Black Bee/Beetle with orange markings on it’s back
Wed, Jun 3, 2009, at 3:19 PM
Was in my garage and killed what I thought was a HUGE bee-looking insect. It could fly and was about 1.25″ long.

Upon closer examination, it was much fatter than a bee or a wasp, had really long antenna that it moved independently was solid black except for 4 distinct orange boxes on its thorax which were like a little shield sitting on its shoulders and were about 1/4 of the insect’s length.

It sat above the lower half of the insect’s abdomen which appeared to me like the thorax of a big wasp. What the heck was that!!!
Kevin
Mukilteo, Washington

Dear Kevin,
We are totally charmed and amused with your artistic rendering of what we are 99 & 44/100% sure is a species of Sexton Beetle or Burying Beetle in the genus Nicrophorus. 

A pair of Sexton Beetles is capable of burying a small corpse like that of a mouse in a short period of time.  According to BugGuide, the Sexton Beetles exhibit “Remarkable parental care of larvae.

Adults bury a small (usually) carcass, lay eggs in it, and stay with it, feeding the young on regurgitated carrion. (Yumm!).” 

Since we are on holiday planting tomatoes in Ohio, we are preparing your letter in advance to post life to our site Sunday at noon.  We will be including a photo sent to us by C.J. last year of a Sexton Beetle.

Letter 7 – Black Burying Beetle

ID for this handsome beetle?
Location:  Paso Robles, California
Date:     January 5, 2011, 1:15:56 PM PST
He was in our bathroom at paso robles on fake flowers… (oaks and chapparal outside).
i loved his red antenna ends (for which i expect there is a technical term!).
Clare Marter Kenyon

Hi Clare,
What died in your bathroom?  This appears to be a Black Burying Beetle, Nicrophorus nigrita, one of the Sexton Beetles. 

Burying Beetles mate and then share the responsibility of burying small animals like mice upon which they lay eggs.  Both parents then care for and guard the young as they feed on the putrefying flesh. 

The antennae are clavate or clubbed (see BugGuide).

Letter 8 – Burying Beetle with Phoretic Mites

Subject: Beetle with some tag-along in Bay Area California
Location: Palo Alto, California
January 12, 2017, 5:54 pm
Hi,
I stumbled on this site while trying to identify a beetle that wandered into our apartment a few days ago on a cold, rainy evening.

It’s black and shiny, and at first, I thought it had some moss on its back, so I put it in a jar to look at it closer and show my 2-year-old son who loves bugs and beetles.

The next morning I discovered all of the little brown dots were not moss, and were indeed animals that were crawling all over the beetle! I put a leaf in which seems to be satisfying both the beetle and the tag-along (aphids?).

Needless to say, I’m curious what beetle this is and why it’d be carrying around dozens of smaller bugs.
Signature: Beetle Dad

Dear Beetle Dad,
This is a Burying Beetle or Sexton Beetle in the genus Nicrophorus.  Most Burying Beetles are black with orange markings, so we believe your all-black individual is the Black Burying Beetle, Nicrophorus nigrita based on images posted to BugGuide where the range is listed as”Pacific US states & so. BC.” 

 The small creatures are Phoretic Mites which use the more mobile Burying Beetle for transportation.