American badger (Taxidea taxus)

The American badger (Taxidea taxus) is a broad, robust mammal with a rather flattened body, a thick neck and short, stout legs ^{(3) (4) (5)}. It has a short, bushy tail, which is patterned yellow-brown ^{(4) (5) (6)}. The American badger has shaggy fur ⁽⁵⁾, and its skin is tough and loose, especially around the shoulders, chest and back, enabling it to turn around in small spaces ^{(3) (4) (7)}.

The fur on the upperside of the American badger can vary from yellow-brown to silver-grey ⁽³⁾, with a white stripe which runs from the nose to a variable point on the neck or back, depending on the subspecies ^{(2) (6)}. The underside also varies between light cream and buff ^{(2) (3)}. The American badger has a distinctive facial pattern which is mostly brown, apart from two white cheek areas and a black triangular patch in front of each ear ^{(3) (6)}. The neck, chin and chest are all whitish ^{(2) (6)}. The backs of the small, rounded ears are black ^{(3) (4)}.

The front feet of the American badger are bigger than the rear feet ⁽⁵⁾ and have longer, backward-curving claws, which are used for digging, while the rear feet have short, shovel-like claws ^{(3) (4)}. All feet have five toes ^{(4) (5)} and are black or dark brown ^{(2) (3) (6)}.

The female American badger is smaller than the male, although both sexes are similar in appearance ^{(2) (3) (4) (8)}. The juvenile American badger is similar to the adult in colouration and patterning ⁽⁵⁾.

Four subspecies of American badger are recognised; Taxidea taxus berlandieri, Taxidea taxus jeffersoni, Taxidea taxus taxus and Taxidea taxus jacksoni, which all differ in range, skull shape and the colour and pattern of the fur ⁽¹⁾. Populations in the north of the range usually have a white stripe which extends from the nose to the shoulders, whereas in populations in the south, this stripe continues down the majority of the back ⁽⁶⁾. 

Size

Male head-body length: 52 - 72 cm ⁽²⁾

Female head-body length: 42 - 64 cm ⁽²⁾

Tail length: 10 - 16 cm ⁽²⁾

Weight

3.5 - 12 kg ⁽²⁾

The American badger is primarily nocturnal, generally foraging at night and remaining underground during daylight hours ^{(1) (3) (6)}. As an adaptation to its partially fossorial lifestyle, the American badger has a third eyelid, known as a ‘nictitating membrane’, which protects the eye from soil ^{(4) (7)}. Its eyesight is poor, although its hearing and sense of smell are acute ⁽⁷⁾.

The burrow systems of this species are used for dens, feeding and as a means of escape ⁽⁸⁾, and the American badger either excavates a burrow itself or modifies one formed by another animal. These burrows can be up to ten metres long and three metres deep ⁽⁶⁾, and usually have a single entrance, which is partially covered in soil. The shallow non-breeding burrows of this species are around 30 centimetres in diameter, with burrows used during the breeding season being much larger and deeper ⁽⁴⁾. An expert digger, the American badger has powerful legs which enable it to dig with remarkable speed, allowing it to disappear from sight rapidly ⁽⁸⁾.

The home range of the American badger, which usually varies in size between 2 and 725 hectares ⁽¹⁾, can become much larger while the male tries to locate receptive females in the area ^{(2) (7)}. Neither sex is territorial and many home ranges are known to overlap ^{(2) (7)}. A typically solitary species, the American badger only comes together as breeding pairs, family groups and as siblings ⁽³⁾. The American badger has well developed scent glands ⁽⁷⁾, which may be used for defence ⁽⁸⁾, or to attract a mate during the breeding season ⁽⁴⁾.

The American badger is a polygamous species and mates in summer and early autumn ^{(5) (6)}. This is followed by a period of delayed implantation, which pauses development of the embryos until February ^{(6) (8)}. The total gestation period is around seven months, although actual embryo development only occurs for around six weeks ⁽⁶⁾.

The female American badger gives birth to a litter of between one and five blind, lightly furred young between March and April ^{(3) (5) (6) (8)}, in an underground nest filled with grass ^{(5) (6)}. The young begin to open their eyes after four weeks and are fully weaned after six to eight weeks ^{(5) (6)}. During this period, the young rarely go above ground, except when the female changes dens, when she will usually carry the young ⁽³⁾. The young remain with the female until the autumn, after which they disperse ⁽⁵⁾.

The American badger does not hibernate, instead reducing above-ground activity by entering a state of torpor in times of bad weather, and surviving on fat reserves when prey is scarce ^{(2) (8)}. If prey is limited, pregnant females must sustain themselves and the growing foetuses on stored fat. Due to this, American badger young are much smaller in relation to the female’s body size than most other mammals ⁽²⁾.

An opportunistic feeder, the American badger has a highly variable diet, consisting mainly of small rodents, such as ground squirrels, voles, mice, pocket gophers, rabbits, marmots and prairie dogs ^{(1) (2) (6) (7) (8)}. Birds and their eggs, as well as reptiles, amphibians and insects, are also taken ^{(1) (6) (8)}. Most rodent prey is acquired by unearthing burrows, and is occasionally buried and saved ⁽⁶⁾. American badgers have been known to join up with coyotes (Canis latrans) and hunt together ^{(2) (8)}.

The range of the American badger stretches from southern Canada to Mexico, including the northern, western and central United States ^{(1) (2) (3) (6)}. Each subspecies is found in a different part of the range: T. t. berlandieri is found in southern USA ⁽¹⁾ and Mexico ⁽⁸⁾; T. t. taxus is found from the Great Plains of the USA into the prairies of Canada; T. t. jeffersoni is found in the western USA and southern British Colombia, Canada; and T. t. jacksoni is found in north-central USA and the south of Ontario, Canada ⁽¹⁾.

The range of the American badger is currently extending eastwards due to land clearance ^{(5) (8)}.

The habitat of the American badger is highly variable ⁽⁵⁾. Relatively dry, open country with very little vegetation is preferred ^{(1) (6)}, such as open plains, prairies, dry grasslands, cold deserts and park lands ^{(1) (2) (3) (5) (7)}, where the badger occupies underground burrows ^{(1) (4)}.

Some populations of the American badger are known to inhabit mountainous areas ⁽⁵⁾, where they are found up to elevations of 3,600 metres ^{(1) (3) (8)}.

The American badger is classified as Least Concern (LC) on the IUCN Red List ⁽¹⁾. 

Throughout the range of the American badger, much of the land has been converted for agriculture ^{(1) (3)}. This has led to this species being seen as a pest in some areas, where the digging of burrows poses a potential threat to livestock, horses and horse-riders, and can cause damage to vehicles ^{(1) (6) (8)}. Burrows can also remove water from irrigation canals used for local agriculture ^{(1) (3)} and make fields more difficult to farm ⁽³⁾.

The American badger is targeted by humans and in some areas a high proportion of mortality is due to poisoning, trapping and shooting ^{(1) (8)}. This species has been affected by the poisoning and destruction of its rodent prey ⁽²⁾, with this thought to be one of the main reasons for the American badger population decline in British Colombia ⁽¹⁾. Road traffic accidents are also frequent and constitute a large proportion of mortalities ⁽¹⁾.

In some areas, urbanisation has reduced the amount of suitable habitat for this species ⁽¹⁾, although clearing of forested areas in the east of its range may be beneficial for some populations ⁽³⁾. Unfortunately, although forest clearance for agriculture has helped the American badger to expand its range in some areas, the future intensification of agriculture and subsequent degradation of habitat is likely to cause population declines ⁽¹⁾.

American badgers were historically trapped for pelts, but this is not thought to constitute a current threat to the survival of this species ^{(1) (6)}. The American badger is very susceptible to parasites such as tapeworms and flukes, as well as diseases such as rabies and tularaemia, an infectious bacterial disease ⁽⁸⁾.

Although this species as a whole is not considered to be globally threatened, two subspecies of the American badger are considered to be locally endangered in Canada, with just 600 T. t. jeffersoni and 200 T. t. jacksoni thought to remain ⁽¹⁾.

More research into the American badger’s role within the ecosystem and its influence on other grassland species is needed ⁽³⁾, and future monitoring of the population has also been recommended ⁽⁵⁾. Some protection is offered to this species in certain parts of its range, although in others it is unprotected, putting the population under threat ⁽³⁾.

To protect the American badger, any development within its habitat should be controlled, and access should be restricted during the breeding season. Any pesticide or rodenticide use should be limited, reducing the threat of ingestion by an American badger or its prey species. Restoration of areas which are currently unsuitable for American badgers could also be an appropriate conservation measure for this species in the future ⁽⁹⁾.

Find out more about the American badger and conservation within its range:

• British Columbia Ministry of Water, Land and Air Protection (2004) Badger (Taxidea taxus jeffersonii). In: Accounts and Measures for Managing Identified Wildlife - Accounts V. 2004. B.C. Ministry of Water, Land and Air Protection, Victoria, British Columbia. Available at:
  http://www.env.gov.bc.ca/wld/frpa/iwms/accounts.html
• U.S. Fish and Wildlife Service:
  http://www.fws.gov/

This information is awaiting authentication by a species expert, and will be updated as soon as possible. If you are able to help please contact:
arkive@wildscreen.org.uk

Delayed implantation

The process of a fertilised egg remaining unattached in the uterus for a period of time, therefore delaying the start of development.

Fossorial

Used to describe an animal that is adapted to living underground, typically one that digs burrows.

Gestation

The state of being pregnant; the period from conception to birth.

Gland

An organ that makes and secretes substances used by the body.

Hibernation

A winter survival strategy in which an animal’s metabolic rate slows down and a state of deep sleep is attained. While hibernating, animals survive on stored reserves of fat that they have accumulated in summer.

Home range

The area occupied by an animal during routine activities, which is not actively defended.

Nictitating membrane

A thin, tough, transparent or translucent membrane, or ‘inner eyelid’, found in various species of birds, reptiles, amphibians and fish, but less common in mammals. The nictitating membrane can be drawn across the eye to protect it from damage, or to moisten the eye while maintaining vision.

Nocturnal

Active at night.

Parasite

An organism that derives its food from, and lives in or on, another living organism at the host’s expense.

Polygamous

Mating with more than one partner in the same season.

Prairie

An extensive area of flat or rolling, predominantly treeless grassland, especially the large tract or plain of central North America.

Subspecies

A population usually restricted to a geographical area that differs from other populations of the same species, but not to the extent of being classified as a separate species.

Territorial

Describes an animal, a pair of animals or a group that occupies and defends an area.

Torpor

A sleep-like state in which the body processes slow to a fraction of their normal rate.

1.  IUCN Red List (April, 2012)
   http://www.iucnredlist.org/
2. Macdonald, D.W. (2006) The Encyclopedia of Mammals. Oxford University Press, Oxford.
3. Feldhamer, G.A., Thompson, B.C. and Chapman, J.A. (2003) Wild mammals of North America: Biology, Management, and Conservation. Second Edition. The Johns Hopkins University Press, Baltimore, Maryland.
4. Schwartz, C.W. and Schwartz, E.R. (2001) The Wild Mammals of Missouri. The University of Missouri Press, Missouri.
5. Schmidly, D.J. (1994) The Mammals of Texas. Texas Parks and Wildlife Department, Texas.
6. Nowak, R.M. (1999) Walkers Mammals of the World.Volume 1.Sixth edition. The Johns Hopkins University Press, Baltimore.
7. Quinn, J.H. (2008) The Ecology of the American Badger Taxidea taxus in California: Assessing Conservation Needs on Multiple Scales. Ph.D. Thesis, University of California, California.
8. Long, C.A. (1973) Taxidea taxus. Mammalian Species, 26: 1-5. Available at:
   http://www.science.smith.edu/msi/pdf/i0076-3519-026-01-0001.pdf
9. British Columbia Ministry of Water, Land and Air Protection (2004) Badger (Taxidea taxus jeffersonii). In: Accounts and Measures for Managing Identified Wildlife - Accounts V. 2004. B.C. Ministry of Water, Land and Air Protection, Victoria, British Columbia. Available at:
   http://www.env.gov.bc.ca/wld/frpa/iwms/accounts.html