The nine-banded armadillo is the only armadillo species found in the United States and one of the most successful range-expanding mammals in the Western Hemisphere. Since first crossing the Rio Grande from Mexico in the mid-nineteenth century, it has spread across the southeastern and central United States and continues to move northward, a distributional shift tracked in detail over multiple decades [Taulman & Robbins 1996; Taulman & Robbins 2014]. Beyond its ecological story, the species occupies a singular place in biomedical science: alongside humans, it is one of the few natural hosts of Mycobacterium leprae, the bacterium that causes leprosy (Hansen's disease), and has become the principal animal model for studying the disease [Storrs 1974; Truman et al. 2011]. This profile examines the armadillo's biology, its expanding range, its conservation status, and the research relevance that has made it a focus of public-health study.
Biology and Identification
The nine-banded armadillo is a medium-sized, armored placental mammal of the order Cingulata. Adults typically have a head-and-body length of 28–50 cm and a tail of 12–45 cm, weighing roughly 3–6 kg [IUCN 2014]. The dorsal surface is covered by a leathery carapace of bony dermal plates (osteoderms) overlaid by keratinized skin; the mid-body region carries movable bands — most often nine, though the count ranges from seven to eleven — that give the species both its common name and a degree of flexibility [IUCN 2014]. The underside and limbs are sparsely haired and unarmored.
Armadillos are primarily insectivorous, using a strong sense of smell to locate beetles, ants, termites, and other soil invertebrates, which they excavate with powerful foreclaws; the diet is supplemented with other invertebrates, small vertebrates, and plant matter [IUCN 2014]. They are prolific burrowers, and a single individual may maintain several burrows that, once abandoned, provide shelter for a range of other wildlife.
The species has a notably low and labile body temperature and a low metabolic rate, traits that constrain its tolerance of sustained cold and help explain the climatic limits on its northward spread [Taulman & Robbins 2014]. When crossing water, an armadillo can either inflate its gut and swim or walk along the bottom of a stream while holding its breath.
A defining feature of Dasypus reproduction is obligate monozygotic polyembryony: a single fertilized egg implants after a delay and then divides to produce a litter of four genetically identical offspring, making the nine-banded armadillo the only mammal known to routinely produce identical quadruplets [Loughry et al. 1998]. This reliable production of natural clones has made the species a model organism for studying developmental variation and individuality among genetically identical individuals [V-Niño et al. 2024].
Habitat and Range
The nine-banded armadillo has one of the widest distributions of any New World mammal, ranging from the central and southeastern United States through Mexico and Central America into much of South America as far south as northern Argentina and Uruguay, and occurring on Trinidad and Tobago [IUCN 2014]. It occupies a broad range of habitats — forest, scrub, grassland, and savanna — from sea level to roughly 2,300 m elevation, and tolerates considerable habitat modification, including agricultural and suburban landscapes [IUCN 2014].
In North America the species is a textbook case of rapid range expansion. After crossing the Rio Grande from Mexico in the mid-1800s, it spread through Texas and the Gulf states and, aided by introductions in Florida, expanded across the Southeast and into the central states [Taulman & Robbins 1996]. A multi-decade reassessment documented continued northward advance into Kansas, Illinois, Indiana, Kentucky, Tennessee, and South Carolina, with the northern limit corresponding closely to minimum winter temperatures; the species reached areas where the mean minimum January temperature approaches roughly −8 °C, and further northward and eastward expansion was projected where that thermal limit had not yet been met [Taulman & Robbins 2014; McDonough & Loughry 2013].
In accordance with NRWL sensitive-species policy, specific site locations, corridor routes, and seasonal movement details are not disclosed in this article.
Conservation Status
The nine-banded armadillo is listed as Least Concern on the IUCN Red List, assessed in 2014, on the basis of its very wide distribution, presumed large population, tolerance of habitat alteration, and the absence of evidence for any major range-wide decline [IUCN 2014]. The global population trend is reported as stable, and in parts of its range — including North America — the species is expanding rather than contracting [IUCN 2014; Taulman & Robbins 2014]. It is hunted for meat in many parts of Latin America but, owing to its high reproductive output, is considered able to withstand a relatively high level of harvest [IUCN 2014].
The species is not listed on any CITES appendix. While several other armadillos are CITES-listed — for example, the giant armadillo (Priodontes maximus) on Appendix I — Dasypus novemcinctus is not included in Appendices I, II, or III [IUCN 2014; CITES 2023].
Because the species is widespread, abundant, and not globally threatened, conservation attention focuses less on preventing decline and more on managing its interactions with people, agriculture, and public health across an expanding range.
Threats
As a Least Concern species with a stable, expanding population, the nine-banded armadillo faces no major range-wide threats [IUCN 2014]. Localized pressures and management concerns nonetheless exist.
Hunting and harvest. Armadillos are hunted for meat throughout much of Latin America. Offtake is generally sustainable given the species' reproductive rate, though it can be locally significant and is compounded by zoonotic-disease risk where infected animals are handled or consumed [IUCN 2014; Sharma et al. 2015].
Road mortality and human conflict. In the United States the species is frequently killed on roads, and its burrowing and rooting can bring it into conflict with landowners; it is treated as a nuisance or game animal in several states rather than a species of conservation concern [McDonough & Loughry 2013].
Interspecific competition. In parts of its North American range, the armadillo overlaps with invasive wild pigs (Sus scrofa), which exploit similar soil-invertebrate food resources; such interactions can locally affect armadillo behavior and resource use.
Disease in wild populations. Naturally occurring M. leprae infection is present in many wild armadillo populations and is the subject of ongoing study of its effects on the animals themselves and its implications for both wildlife health and human exposure [Sharma et al. 2015; Ferreira et al. 2025].
What Is Being Done
Because the species is not at risk, formal recovery programs are not required; the relevant work centers on monitoring, management, and the public-health science surrounding armadillo-associated leprosy.
Distribution monitoring. Long-term tracking of the North American range — through field surveys, biologist questionnaires, and occurrence records — has produced one of the best-documented mammalian range expansions on the continent and continues to refine projections of future spread under changing climate [Taulman & Robbins 1996; Taulman & Robbins 2014].
Leprosy research and surveillance. The armadillo is the principal animal model for M. leprae, which does not grow in standard laboratory culture; experimental infection of armadillos, first established in the early 1970s, remains the main means of propagating the bacterium and of studying the pathogenesis of the disease, including its characteristic peripheral-nerve involvement [Storrs 1974; Sharma et al. 2013]. Genomic studies have shown that strains of M. leprae in wild armadillos and in autochthonous human leprosy cases in the southern United States are essentially identical, establishing the armadillo as a natural reservoir and a probable source of zoonotic infection [Truman et al. 2011; Sharma et al. 2015]. This work supports public-health guidance and diagnostic and vaccine research [Truman 2014].
Wildlife-health science. Systematic review of M. leprae infection in wild Dasypus populations is helping clarify how the disease affects armadillo populations and how infection prevalence varies geographically — information relevant to both conservation biology and human exposure risk [Ferreira et al. 2025].
Public guidance. Health agencies advise the public to avoid handling or consuming wild armadillos in regions where the animals carry M. leprae, framing the risk factually and noting that overall human infection risk from incidental contact is low [Sharma et al. 2015].
How Readers Can Help
Citizen science. Record armadillo sightings — including road-killed animals — through platforms such as iNaturalist. Verified occurrence records are a primary data source for mapping the species' continuing range expansion and refining distribution models [Taulman & Robbins 2014].
Informed coexistence. In areas where armadillos are expanding, address burrowing in gardens and yards with humane exclusion and habitat modification rather than indiscriminate killing. Most armadillo activity is harmless soil foraging.
Reduce zoonotic risk responsibly. In regions where wild armadillos can carry M. leprae, avoid handling or consuming them. The risk to people is low and should be communicated factually, without stigma toward the animals, which are an important part of native ecosystems [Sharma et al. 2015].
Support science-based wildlife management. Back agencies and programs that monitor wildlife distributions and zoonotic disease, and that base management decisions on peer-reviewed evidence rather than perception.
Share accurate information. Help correct common misconceptions — for example, that all armadillos carry leprosy, or that the species is endangered. Conveying that the nine-banded armadillo is a widespread, Least Concern species with a localized public-health dimension supports both sound policy and public understanding.
References
[CITES 2023] CITES. (2023). Appendices I, II and III. Convention on International Trade in Endangered Species of Wild Fauna and Flora. https://cites.org/eng/app/appendices.php
[Ferreira et al. 2025] Ferreira, J.d.S., et al. (2025). Impacts of Mycobacterium leprae-Infection on Wild Populations of the Nine-Banded Armadillo (Dasypus novemcinctus) Species Complex: A Systematic Review. Diversity, 17(8), 582. https://doi.org/10.3390/d17080582
[IUCN 2014] Loughry, J., McDonough, C. & Abba, A.M. (2014). Dasypus novemcinctus. The IUCN Red List of Threatened Species 2014: e.T6290A47440785. https://doi.org/10.2305/IUCN.UK.2014-1.RLTS.T6290A47440785.en
[Loughry et al. 1998] Loughry, W.J., Prodöhl, P.A., McDonough, C.M. & Avise, J.C. (1998). Polyembryony in Armadillos. American Scientist, 86(3), 274–279. https://doi.org/10.1511/1998.3.274
[McDonough & Loughry 2013] Stangl, F.B., Jr. (2013). Review of The Nine-Banded Armadillo: A Natural History by W.J. Loughry & C.M. McDonough (University of Oklahoma Press, 2013). Journal of Mammalogy, 95(2), 432–433. https://doi.org/10.1644/13-MAMM-R-228
[Sharma et al. 2013] Sharma, R., Lahiri, R., Scollard, D.M., Pena, M., Williams, D.L., Adams, L.B., Figarola, J. & Truman, R.W. (2013). The armadillo: a model for the neuropathy of leprosy and potentially other neurodegenerative diseases. Disease Models & Mechanisms, 6(1), 19–24. https://doi.org/10.1242/dmm.010215
[Sharma et al. 2015] Sharma, R., Singh, P., Loughry, W.J., Lockhart, J.M., Inman, W.B., Duthie, M.S., Pena, M.T., Marcos, L.A., Scollard, D.M., Cole, S.T. & Truman, R.W. (2015). Zoonotic Leprosy in the Southeastern United States. Emerging Infectious Diseases, 21(12), 2127–2134. https://doi.org/10.3201/eid2112.150501
[Storrs 1974] Storrs, E.E., Walsh, G.P., Burchfield, H.P. & Binford, C.H. (1974). Leprosy in the Armadillo: New Model for Biomedical Research. Science, 183(4127), 851–852. https://doi.org/10.1126/science.183.4127.851
[Taulman & Robbins 1996] Taulman, J.F. & Robbins, L.W. (1996). Recent range expansion and distributional limits of the nine-banded armadillo (Dasypus novemcinctus) in the United States. Journal of Biogeography, 23(5), 635–648. https://doi.org/10.1111/j.1365-2699.1996.tb00025.x
[Taulman & Robbins 2014] Taulman, J.F. & Robbins, L.W. (2014). Range expansion and distributional limits of the nine-banded armadillo in the United States: an update of Taulman & Robbins (1996). Journal of Biogeography, 41(8), 1626–1630. https://doi.org/10.1111/jbi.12319
[Truman et al. 2011] Truman, R.W., Singh, P., Sharma, R., Busso, P., Rougemont, J., Paniz-Mondolfi, A., Kapopoulou, A., Brisse, S., Scollard, D.M., Gillis, T.P. & Cole, S.T. (2011). Probable Zoonotic Leprosy in the Southern United States. New England Journal of Medicine, 364(17), 1626–1633. https://doi.org/10.1056/NEJMoa1010536
[Truman 2014] Sharma, R., Lahiri, R., Scollard, D.M., Pena, M., Williams, D.L., Adams, L.B., Figarola, J. & Truman, R.W. (2014). The armadillo as an animal model and reservoir host for Mycobacterium leprae. Clinics in Dermatology, 33(1), 108–115. https://doi.org/10.1016/j.clindermatol.2014.07.001
[V-Niño et al. 2024] Vázquez-Niño, D., et al. (2024). What makes each of us unique? The nine-banded armadillo as a model to study individuality. Frontiers in Mammal Science, 3, 1450655. https://doi.org/10.3389/fmamm.2024.1450655