Dasypus novemcinctus
nine-banded armadillo

D. novemcinctus is found from Peru and northern Argentina to the south-central and southeastern United States. It is also found on the islands of Grenada, Trinidad and Tobago. It has been expanding its range to the north, into the United States, since the mid-19th Century.

D. novemcinctus lives in a wide variety of habitats over its geographic range.

The most notable physical characteristic of D. novemcinctis (and all armadillos) is the leathery skin and ossified dermal plates on the back, sides, tail and top of the head that form a turtle-like carapace. This carapace is divided into three sections: a scapular shield, a pelvic shield, and a series of telescoping "bands" around the mid-section. The bands are connected by soft, hairless skin and the anterior edge of each band is overlapped by the preceding band. Despite the common name, D. novemcinctus can have as few as 7 or as many as 11 bands. In the northern and southern portions of the range eight bands are the norm and nine bands are normally only found in the central portion of the range. The tail is covered by 12 to 15 rings. The ears are about half the length of the head and covered with tough skin. The head is pointed and ends in a pig-like snout. The forefeet have 4 digits and the hindfeet have 5 digits. The toes have long, sharp, curved claws useful for digging. The limbs are short and stout, also useful for digging. D. novemcinctus has no incisors or canines and the teeth are single rooted and peg-like. The adult teeth do not have enamel. Males tend to be slightly larger than females. Females range in weight from 3.6 to 6 kg; males range from 5.5 to 7.7. Some other measurements are: total length, 616-800 mm; tail length, 245-370; hindfoot length, 75-107 mm; ear length, 40 mm; skull length, 85.5-100 mm.

Nine-banded armadillos are nocturnal or crepuscular. Temperature, not light, appears to be the signal initiating activity. Smell is the main sense used in foraging. Armadillos prowl with the snout close to the ground and root with the snoot or dig with the claws when food is found in the ground. Armadillos construct burrows, which may be occupied by several animals, usually of the same sex. Burrows are also often shared with other mammals such as rabbits, skunks and possums. D. novemcinctus is not territorial. Home ranges of 12 animals in Florida averaged 5.7 ha, ranging from 1.1 to 13.8 ha. Ranges overlapped and no antagonism was observed between individuals, further supporting the idea that they are not territorial. Contrary to popular belief, nine-banded armadillos do not curl up into a ball when threatened. They have been reported to outrun hunters and dogs. When chased into a burrow they wedge themselves in by arching the back against the burrow walls and are impossible to dislodge. When confronted by a water barrier, armadillos have two means of crossing. If the water is shallow and narrow, armadillos can walk or run across the bottom because their specifc gravity is 1.06. To cross deeper or broader stretches of water, armadillos gulp air into the digestive tract and swim like a dog.

The nine-banded armadillo principally eats animal matter, including ants, beetles, other artropods, small reptiles and amphibians. Birds and small mammals will occassionally be eaten, as will carrion. Some plant matter, principally fruit, berries and debris round out the diet.

Nine-banded armadillos do some damage to crops and occassionally eat ground-nesting birds. They have also been accussed of eating quail and turkey eggs, though the evidence is weak. They might be vectors for leprosy.

Armadillos have a number of positive aspects. First, they are a common food item in parts of the southern US and Latin America. Next, they consume many noxious and harmful insects. Lastly, they are valuable for use in medical research on multiple births, organ transplants, birth defects and diseases such as leprosy, typhus and trichinosis.

The first occurrence of D. novemcinctus in the United States was in 1854 along the Rio Grande. It has been expanding to the north since. Possible explanations for the range expansion include climate change and human mediated modification of habitats by overgrazing of livestock and predator removal. D. novemcinctus is the only mammal besides humans that suffers from lepromatid leprosy.