On cloudy or rainy days when temperatures are warm, the armadillo roots around in search of food throughout the daylight hours.
Woodlands provide shady grubbing areas on clear, hot days, but when the temperature gets too high, the armadillo heads for the cooler comfort of its burrow and waits for twilight and the night hours for foraging.
Winter is just the reverse. The armadillo goes out to feed only during the day when the winter sun provides some warmth. Burrows provide some protection from bad weather, but time spent below ground is limited by the armadillo's need to forage daily. While feeding, the armadillo digs cone-shaped pits about three or four inches deep, laps up any exposed insects before moving on, then revisits the pits regularly to claim any insects they may have trapped. The armadillo's twelve- to seventeen-pound body requires a lot of food, so the time spent above ground is occupied by searching for food.
It would be rare indeed to find an undisturbed armadillo that was not foraging. Normally the armadillo wanders about in a rambling, unhurried manner. If left alone, it travels no more than one-third mile per hour, but when danger threatens, it can turn on the speed and is a master at dodging.
Unlike some of its South American relatives, the nine-banded armadillo does not roll into a tight ball for protection. Unless injured or exhausted, it runs when frightened. During its continuous and dedicated search for food, the armadillo seems unaware of its surroundings. Its tiny eyes may be partially closed or half buried in vegetation as it roots along. Even when the eyes are exposed, its eyesight can only be considered poor. A feeding armadillo, sensing danger, may stand up on its hind legs, bracing itself with its tail, and appear to look around while sniffing the air for enemies.
However, it can look directly at someone who is standing still and give no indication that it sees anything. If the person remains motionless and makes no noise, and if the human scent does not reach the armadillo, the creature probably will resume feeding.
If startled, an armadillo may respond by leaping straight up before running. One observer, who pitched small rocks one at a time at a feeding armadillo, reported that the animal leaped into the air after each rock landed, then stood up and sniffed the air for danger.
Feeding activity resumed shortly after each jump when no enemy was scented or seen. After several rocks had landed nearby, the fact that the disturbances might mean danger finally seemed to penetrate its brain, and it took off at high speed. This nervous jumping response probably is responsible for many of the road-killed armadillos. Even when the motorist is able to straddle the animal with the vehicle's wheels, the upward leap brings the armadillo's body into contact with the car's understructure, breaking the shell and causing fatal injuries.
Armadillos cannot be considered stealthy animals by any stretch of the imagination. Many a hunter has been disappointed when the herd of deer he thought was heading for his stand turned out to be a snuffling, shuffling armadillo rooting its way through leaves and other woodland debris.
As if that weren't noisy enough, the armadillo also may make low grunting sounds as it digs for food. A keen sense of smell enables the near-sighted armadillo to locate grubs, beetles, insects, snails, worms, ants, and other such gourmet delights that may be buried beneath six inches of soil.
Its long, sharp claws — four on the front feet and five on the rear ones — can dig even the most elusive tidbit out of the soil or rotten wood; and its finely barbed, sticky tongue is perfect for picking them up.
Although it also eats berries and some other vegetation, its rooting and digging for insects are what bring the armadillo into conflict with humans. Few people looking at damaged lawns, flowerbeds, and gardens are consoled by the fact that the armadillo causing the damage was only searching for bugs — grubs that may be harmful to those same lawns, flowers, and gardens, but not in such an obvious way. While feeding, the armadillo digs cone-shaped pits, usually no more than three or four inches deep.
It laps up any insects it finds in the soil before it moves on in search of other places to dig. Sporothrix schenckii and sporotrichosis.
Anm Acad Bras Ciencias ; Epidemiology of sporotrichosis in Latin America. Clinical and Laboratory Standards Institute. Reference method for broth dilution antifungal susceptibility testing of filamentous fungi.
Approved standard Document MA2. Wayne, P. Practice guidelines for management of patients with sporotrichosis. Subcutaneous bilateral sporotrichosis: a rare presentation. Arenas R. London: Edward Arnold Publishers; Isolation of Sporothrix schenckii from nature and considerations on its pathogenicity and ecology.
Vidal G, Rodriguez-de-Kopp N. Arch Argent Dermatol ; Gezuele E, Rosa D. Rev Iberoam Micol ; Lavalle P. In vitro susceptibility of Sporothrix schenckii to six antifungal agents determined using three different methods. Antimicrob Agents Chemother ; In vitro antifungal susceptibilities of five species of Sporothrix Antimicrob Agents Chemother ; Address to: Prof.
Females constantly appear to retreat from males, which may be an effort to prevent the male from keeping too close before she is ready to mate. The secretions by the anal glands may have a scent that changes as a female becomes ready to ovulate. Some observational studies have shown that within a given breeding season, nine-banded armadillos are polygnous with respect to pairing, however, pairing may not lead to copulation. This is a topic still under study.
Loughry, et al. Females have a large external clitoris, while males lack an external scrotum and testes are internal. The female reproductive tract includes a simplex uterus and paired ovaries and oviducts. Most females ovulate once a year, usually in early summer June to July in the northern hemisphere, November to December in the southern hemisphere. Copulation occurs during this time of year, with the female positioned on her back.
During conception, only a single ovum is fertilized. The blastocyst stays in the uterus for about 14 weeks before implantation. During this time, fluids from the uteran lining keep the blastocyst lubricated and provide nutrients. Nine-banded armadillo reproduction involves monozygotic polyembryony. That is, when a blastocyst finally implants in the wall of the uterus, it buds into 4 identical embryos.
Every embryo develops its own amniotic cavity. This embryonic process almost always results in the birth of four identical quadruplets. Chapman and Feldhamer, The quadruplets are often born in early spring, after about a 4 month gestation period. Delayed implantation allows birthing to happen during the spring, when temperatures are much warmer and food is abundant. Chapman and Feldhamer, ; Macdonald, Young are born in an advanced state of development, closely resembling their adult counterparts but smaller in size.
The eyes open quickly, but their leathery skin does not harden into its characteristic armor for a few weeks. Young of both sexes may begin breeding as early as the summer following their birth, but they may not reach full sexual maturity until the age of 2 years. Full development and maturity is attained by the age of 3 or 4 years.
Young are typically born in spring but do not leave their burrows until late spring or early summer, after at least a few weeks. When they emerge, they are ready to begin foraging with their mother.
The mother may provide milk for up to 2 to 3 months before weaning. After weaning the young may remain with their mother for a few additional months, but no significant long term care or parent-offspring relationship is known. A young nine-banded armadillo may share a burrow and foraging areas with its siblings during its first summer and early fall. Reported life expectancies of nine-banded armadillos range from as low as 7 to 8 years to more than 20 years.
At least one nine-banded armadillo in captivity reached 23 years of age. Juveniles have a higher mortality rate than adults. The factors influencing longevity of nine-banded armadillos include climate, predation, and disease. Because this species does not have a significant amount of hair or body fat, it does not cope well with cold temperatures.
The larger the animal, the more likely it will survive colder temperatures. Other environmental conditions, such as drought, also have an impact on nine-banded armadillo mortality.
In one area that experienced a severe drought, the nine-banded armadillo population completely disappeared due to death or migration McDonough and Loughry, Predation and death by humans, both purposeful and accidental, are other causes of mortality. A juvenile is more likely to be killed by a predator in the wild than is an adult due to its weaker physical state and softer armor.
McDonough and Loughry, ; McDonough, Disease can be an important contributor to nine-banded armadillo mortality; leprosy, in particular, has an important impact. Nine-banded armadillos are nocturnal or crepuscular but forage earlier in the day during cold or cloudy periods. They do not hibernate, but in the northern part of their distribution, nine-banded armadillos are more active during summer months. They cross streams or rivers by swimming or simply walking across the bottom.
An armadillo can accumulate a large oxygen debt and hold its breath for up to 6 minutes. By swallowing air, the animal can also regulate its buoyancy to some degree.
Armadillos tire quickly, however, and cannot cross wide bodies of water. Nine-banded armadillos dig burrows by loosening soil with their noses and forelimbs and then kick the soil away with their hind limbs. A burrow may have several entrances, but there is a main entrance that the animal preferentially uses. Burrows are between 1 and 5 m in length and located a few cm to 2 m below ground.
Nine-banded armadillos may have multiple burrows, including one for nesting and several shallower ones used as food traps. Nine-banded armadillos also use naturally occurring above-ground crevices as nesting sites. The animals carry nesting materials, such as twigs and leaves, by clutching items to themselves with their forelimbs and hopping bipedally. Rotting materials may be removed after heavy rainfall. Aside from mating pairs or a mother with a very young litter, nine-banded armadillos typically do not share burrows.
However, incidences of non-related adults sharing a nest have been documented in cold weather, and it is speculated that this may be a way for these armadillos to thermoregulate at the northern limits of their distribution. Nine-banded armadillos are rarely aggressive toward one another, although a pregnant or nursing mother may be unusually aggressive, even toward her own older offspring.
During the mating season, older males occasionally exhibit aggressive behavior toward younger males. Aggressive behavior, such as kicking or chasing, usually does not result in serious injury. When agitated by a perceived threat, nine-banded armadillos usually freeze. They can also jump up straight in the air and sprint over short distances.
A frightened nine-banded armadillo usually seeks a burrow, and once inside, arches its back and braces its feet so that it is difficult to remove. If a burrow is not nearby, the animal may seek dense thorny underbrush, as it is relatively protected by its tough exterior.
While nine-banded armadillos curl up, they are not capable of curling itself into a perfect ball like other species, such as three-banded armadillos. Estimates for the home range size of nine-banded armadillo range from 0. This variation in size is attributable to physical conditions of the surrounding land, such as soil type and water availability. Home range size is also believed to increase with age.
Female and male home ranges tend to be of similar size, although adult males tolerate much less overlap. Adults of both sexes may share home ranges with juveniles and members of the opposite sex. A small number of individuals are transient. Chapman and Feldhamer, ; McDonough and Loughry, Olfaction is the primary mode of perception used by nine-banded armadillos. Olfaction is essential while foraging. Nine-banded armadillos travel with their nose just above the ground and can smell invertebrates up to 20 cm below the surface.
They can also stand bipedally, bracing themselves with their tail and sniff the air to locate food. Smell may also be important for nine-banded armadillos to orient themselves and recognize familiar places, although there is no evidence that they employ scent trails.
Chapman and Feldhamer, ; Moeller, Nine-banded armadillos also have a good sense of hearing, which the animals use in avoiding predation or other sources of potential danger.
Nine-banded armadillos have a poor sense of vision, which is useless except at close distances, and they are thought to have a poor sense of touch. Dasypodidae species have fewer taste buds than other mammals , so it is likely that nine-banded armadillos have a poor sense of taste as well. First, armadillos will eat carrion, which in the US is often roadkill. Animals that eat roadkill often become roadkill themselves, because they are on the road more often than other animals are. Second, armadillos are nocturnal.
It is hard to see animals by the side of the road at night, so it is harder for motorists to avoid hitting them. Third, armadillos jump up in the air when they feel threatened. In the US, armadillos can be found all over the Southeast. They are scarce in the drier areas of Texas, and are not currently found west of the Rockies.
The northernmost places that armadillos have been spotted are Nebraska the southern tip of Indiana, although this are probably isolated cases and not established populations. Due to their inability to withstand extremely cold weather, it is not likely that they will increase their range any further north than Nebraska in the midwest.
They could spread farther to the northeast, and would probably do well as far north as Vancouver if intorduced to the west coast. For more information, see the Armadillo Expansion page. I know of no company or restaurant that sells live armadillos. They range from brown to khaki to a pebbly grey. For a better color description, go to the Armadillo Species page, and look at the pictures there to see for yourself. The best information I have about the lifespan suggests up to 20 years in captivity for the nine-banded armadillo.
Extrapolating from other similar-sized mammals, I would guess that the average lifespan in the wild would be between five to seven years. Lifespan information for many of the armadillo species are included on the Armadillo Species page. An adult nine-banded armadillo is about the same size as an average housecat. The body length ranges from 15 to 17 inches; the tail is 14 to 16 inches long. They weigh between 8 and 17 pounds; males are heavier than females.
Weight and body length information for all of the armadillo species are included on the Armadillo Species page. Yes and no. The nine-banded armadillo nearly always gives birth to four identical pups, just as humans nearly always give birth to one child at a time.
However, just as people sometimes give birth to twins, armadillos will occasionally bear litters of three or five pups. Despite the number, the pups are always identical.
They form from the same egg, share the same placenta during development, and are all the same sex. The identical quadruplets make armadillos valuable to medical researchers as an animal model for multiple births. Members of the genus Dasypus , including the nine-banded and seven-banded armadillos, are the only ones that exhibit polyembryony.
Other types of armadillo, like the giant or six-banded armadillos, only produce one baby per fertilized egg. For more information on the dietary habits of armadillos, see the Armadillo Species page.
Farmers have blamed armadillos for ruining melon crops, among other things. Raccoons are probably the biggest culprits.
Armadillos seem to suffer from the same problem that hyenas do — their bad reputation appears to be a result of being in the wrong place at the wrong time. Hyenas were long thought to be scavengers, because when naturalists observed them at dawn on the savanna, they were seen skulking around behind the lions feasting on a fresh kill.
Thanks to night observations, we now know that the lions often steal a carcass that the hyenas actually hunted down and killed. The giant armadillo is considered an agricultural pest by some South American farmers.
They do eat some fresh shoots, but mostly are responsible for digging up fields in search of insects. Game hunters have suggested that the decline in population of ground-nesting birds is related to armadillo predation.
The rise in the cat population in the US is probably much more to blame; feral cats and housecats alike are wreaking havoc on the small animal populations worldwide. As for the adults — well, see the next question….
Many different kinds of mammals have special names for males such as buck, ram, bull, boar, and so on and for females such as ewe, dam, cow, doe, and so forth.
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