By Arielle Parsons and Alexus Berndt on December 15, 2016
There are twenty armadillo species in the world and all live exclusively in Latin America, except one. The nine-banded armadillo has been slowly but steadily making its way north from Central and South America. In fact, it has recently made it all the way to North Carolina! It was first sighted in the state in 2008 and since then its expansion has continued, covering twelve counties in the western and southern portions of the state. In 2013, the North Carolina Wildlife Commission sought help from the public in documenting observations of the species statewide.
So what has allowed this expansion? Prior to the mid 1800’s, natural physical barriers like the Rio Grande and large, sweeping fire-maintained grasslands kept the nine-banded armadillos confined to Central and South America. In the latter half of the century, European colonists settled Southern Texas, removing many of the previous barriers and allowing the species to move into the United States. Following this initial movement into the country, range expansion was likely accelerated by human travel and commerce in and out of Southern Texas through the development of roads and railroads.
Studies of current expansion patterns have lead scientists to believe that it will likely continue. Armadillos have very high reproductive rates, high dispersal rates and few predators which contribute to rapid spread and establishment in new, suitable habitats. They are predicted to continue expanding as far north as Connecticut on the east coast and Nevada in the west. Weather factors, and therefore climate change, will play a huge factor in how far the species will expand its range. Their body lacks thick insulation so temperature plays a large role in dictating their activity.
Armadillos are distinct and easy to spot, they are roughly the size of a housecat, weighing anywhere between eight to seventeen pounds. Gray to brownish-gray in color, they have narrow jointed armor bands across the midsection. Although they are named the nine-banded armadillo, their bony armor many include seven to eleven movable rings between the shoulder and hip shield. Their small eyes offer poor eyesight, but their pointed, shovel shaped snout makes up for that with a keen sense of smell. Armadillos prefer habitats with dense, shady cover including brush, woodlands and forests. The species can be nocturnal, crepuscular or even active during the day to adapt to temperatures that best fit their needs.
The expansion of the nine-banded armadillo is a mixture of natural expansion and purposeful introduction by humans (for example in Florida). It raises some concerns because of the potential for nuisance behavior. Their diet is made up of insects and grubs that it must dig for with its strong legs and huge front claws. This digging can result in substantial damage to lawns, golf courses, vegetable gardens and flower beds. The key sign of armadillo activity is the presence of shallow holes, one to three inches deep and three to five inches wide. Soil texture is a large factor in habitat preference for this species. They favor loose and porous textures that are easy for digging. Armadillos also like to burrow, preferring areas with an abundance of cracks, crevices or rock. Sometimes this may be under foundations which can lead to structural damage to buildings.
One factor to be aware of as this species continuous to expand its range is that armadillos are one of the few mammal species that can carry and transmit Mycobacterium leprae – the bacteria known to cause leprosy. Although the CDC reports that the number of armadillo-human transmitted cases of leprosy is extremely low, it’s a good idea to handle armadillo encounters, either with live or dead specimens, with gloves and a great deal of care to protect against the possible spread of disease.
The Candid Critters mission is to deploy camera traps in all 100 counties of North Carolina, which will be instrumental in determining the species’ current range in the state and learn more about their ecology. If you are interested in becoming a citizen scientist and learning more about mammal species in North Carolina, visit http://www.nccandidcritters.org to sign up!