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American Burying Beetle

 

Jump to a section: Reproduction and development, range, and population level | How to identify an American burying beetle & links | Management considerations | Recent actions & links | « Back to invertebrates | Open / close all

American burying beetle (Nicrophorus americanus)

Family: Silphidae

Description: The American burying beetle is a large black insect with two distinct orange bands on each elytra (wing covers).  The pronotum (shield-like structure behind the head) is orange with a black border. Each antennae is tipped with orange and there is an orange patch on the head. This large beetle is about 1.5 inches long.

Status: The American burying beetle was listed as an endangered species in 1989 (Federal Register 54:29652-29655).

Habitat: Considering the broad geographic range formerly occupied by the American burying beetle, it is unlikely that vegetation or soil type were historically limiting. Today, the American burying beetle seems to be largely restricted to areas most undisturbed by human influence. 

Carrion availability (appropriate in size as well as numbers) may be the more important factor of where beetles occur than the type of vegetation or soil structure. Habitats in Nebraska where these beetles have been recently found consist of grassland prairie, forest edge and scrubland. Specific habitat requirements are unknown.


Reproduction and development, range, and population level »

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Reproduction and development: Adults become active in early summer. These carrion beetles lay their eggs in the carcass of small animals. A male and female pair locate a carcass of appropriate size using olfactory (smell) organs located in their antennae. The carcass is moved to a substrate soft enough to bury the corpse. The pair work to remove soil from beneath the carcass until it settles into a shallow grave several inches below the ground surface. After removing feathers or fur, the beetles secrete a substance that slows the decomposition of the carrion. The corpse is then buried but the female creates a small chamber above the carcass where she lays from 10 to 30 eggs.  

The larvae receive parental care during the entire time they are feeding and growing. This is an extremely rare behavior in insects, a condition normally found only in the social bees, wasps, ants and termites. Both adults regurgitate food to begging larvae. The larvae grow rapidly and are soon able to feed themselves. The adults continually tend the carcass, removing fungi and covering the carrion ball with an antibacterial secretion. Sometimes the size of the brood is too large to be successfully reared on a small carcass, and both adults will cannibalize small larvae. After about a week, the larvae have consumed all but the bones of the carcass, and the adults fly away. Adults live only one season. The young pupate in the nearby soil and emerge as adults about a month later. Beetles overwinter in the adult stage.

Of principal importance to the beetles and their young is burial of the food resource, which effectively removes it from intense competition by maggots, other carrion-feeding insects and even mammal scavengers.

Range: The American burying beetle has been recorded historically from at least 150 counties in 35 states in the eastern and central United States, as well as along the southern fringes of Ontario, Quebec and Nova Scotia in Canada.  The American burying beetle has been found in four states: Nebraska, Rhode Island, Oklahoma and Arkansas.  In recent years it has also been found in three counties in South Dakota and a few beetles found in Kansas.

Population level: There are perhaps fewer than 1,000 individuals in the only remaining population east of the Mississippi River, and the Oklahoma, Arkansas and South Dakota populations (currently being inventoried) are of uncertain size.  South Dakota estimates over 500 square miles of occupied habitat with a high population density.  The Nebraska population occupies a large geographic area of the Sand Hills.


How to indentify an American burying beetle »

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Did you find an American burying beetle or something else?

The ABB has orange on the pronotum (the segment between the head and the body). If the beetle you are looking at does not have orange in that area, it is not an ABB. Other more common burying beetles that look very similar include: Nicroporus marginatus, Nicrophorus orbicollis, and Nicrophorus vestigator. Please check with your local entomologists if you need help with a correct identification of the burying beetles you find.

Infographic showing how to identify an American burying beetle.

Management considerations »

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The cause for the decline of the species is complex and difficult. However, in order to implement an effective recovery program and to locate additional populations, it is necessary to understand the possible factors influencing the decline.

The decline of the American burying beetle is probably the result of an interplay of several complex factors that include (1) artificial lighting that decreases populations of  insects active at night, (2) changing sources of carrion because of habitat alteration, (3) isolation of preferred habitat because of land use changes, (4) increased edge effect harboring more vertebrate competitors for carrion and (5) the possibility of reduced reproduction because of some genetic characteristic of the species.

Fragmentation of large expanses of natural habitat changed the species composition and lowered the reproductive success of prey species required by the American burying beetle for optimum reproduction. Fragmentation also resulted in an increase in edge habitat that supported and increased the occurrence and density of vertebrate predators and scavengers such as crows, raccoons, foxes, opossums and skunks, all of which compete with the burying beetle for available carrion. Fragmented habitats not only support fewer or lower densities of indigenous species that historically may have supported burying beetle populations, but there is also now a great deal more competition for those limited resources among the "new" predator/scavenger community.

The U.S. Fish and Wildlife Service, in cooperation with the scientific community, has formulated a recovery plan that is now being implemented. Surveys at several places in the eastern United States are being conducted to find remnant populations so they can be protected from land development authorized or funded by state and federal agencies. The search for remnant populations is now the primary activity in Nebraska. The populations in Rhode Island, Arkansas and Oklahoma are being monitored, and the habitats there are being managed to prevent any disruption that might be harmful.

Beetles are being reintroduced in Massachusetts from a laboratory colony at Boston University, and other introductions are planned.  Life history studies are being conducted in order to determine possible factors responsible for the decline of the species. Similarly, DNA studies are ongoing to ascertain what, if any, genetic differences exist among the known populations. Knowledge of those differences could be important for future breeding programs. Finally, a public education program has been developed to increase awareness of the importance of this unique insect.


Recent actions & links »

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Recovery Plan (6.76 MB)
National USFWS Web Page
Habitat Conservation Plans (21 KB)

South Dakota Game, Fish and Parks American Burying Beetle website

Information summarized from:

NatureServe Explorer: An online encyclopedia of life [web application]. 2001. Version 1.6 . Arlington, Virginia, USA: NatureServe. Available: http://www.natureserve.org/explorer. (Accessed: August 14, 2002 ).

U.S. Fish and Wildlife Service. 1991. American Burying Beetle (Nicrophorus americanus) Recovery Plan. Newton Corner, Massachusetts. 80 pp.

USFWS American Burying Beetle Species Profile page

 

The mission of the U.S. Fish and Wildlife Service is working with Others to conserve, protect, and enhance fish, wildlife, plants and their habitats for the continuing benefit of the American People.
Last modified: April 08, 2015
All Images Credit to and Courtesy of the U.S. Fish and Wildlife Service Unless Specified Otherwise.
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