The armadillo, an ancient mammal that first appeared 65 million years ago, is currently represented by approximately 20 different species, the most common of which in the US is the nine-banded armadillo. It averages 0.75 m in length (including the tail) and 6 kg in weight. The armadillo boasts a unique carapace, or hard, protective outer shield encasing the body, covered with a dark brown keratin layer. Beneath this layer is a well organized arrangement of bony tiles that are closely compacted and connected by collagen fibers. The carapace is divided into five regions: head, pectoral, banded, pelvic shields and tail. The tiles are hexagonally shaped in the pectoral and pelvic regions and triangular along the mid-section.
The nine-banded armadillo is distributed from northern Argentina to the southern US, living in a wide range of environmental conditions. The armadillo is most active at dusk and during the night in order to avoid predators and extremes of temperature, though this varies with climate and seasonality. The nine-banded armadillo, compared with most eutherian mammals, has an atypical endothermy characterized by low and variable metabolic rates and body temperatures. Some armadillos are insectivores, but many species, like those of the genus Dasypus, also feed on fruits, roots and small vegetables. Armadillos swallow their prey together with soil particles, which provide iron.
Armadillos dig burrows for their homes or to escape predators, and a single armadillo can have several different burrows with multiple entrances. Pregnant females always give birth to identical quadruplets. She produces one egg that splits into four identical offspring that are either all female or all male. This trait differs from most other mammals.
Armadillos are fascinating in other respects. When they need to cross narrow water bodies, they often walk on the bottom underwater. If it is a wide body of water, they will inflate their stomach to twice its normal size, allowing for enough buoyancy to swim across. When startled, armadillos often leap high into the air, and then run quickly to a nearby burrow.
Armadillos are largely insectivores but may consume fruit when available. Their skull, jaw and teeth are adapted to a specialized diet. Their tongue is sticky with rear facing hooks giving the tongue a rough texture. The armadillo’s diet consists mainly of invertebrates including insects (beetles, wasps, moth larvae) and also ants, millipedes, centipedes, snails, leeches, and earthworms. The exact composition varies by season, availability and geographic locations. Studies show they also consume fruit, seeds and other vegetable matter. They have been reported to consume newborn rabbits and at least one robin. It is unknown if they merely found these animals dead or not. Other items known to be consumed by armadillo include salamanders, toads, frogs, lizards, skinks, and small snakes.
The sex ratio by litter is 1 male litter (= 4 identical quadruplets) per 0.78 female litters in Florida. Armadillos probably live 6 to 7 years in the wild. Population density is about one animal per 4 acres but could range as high as two animals per acre.
Problems with armadillos
Armadillos prolific rooting and burrowing can damage lawns and flower-beds. To reduce armadillo damage to your lawn, keep watering and fertilization to a minimum. Moist soil and lush vegetation bring earth worms and insect larvae to the surface of the soil. Armadillos can sometimes be enticed to move on by watering areas adjacent to the damage site. Also, watering gardens in the morning is preferable since the soil can dry out in the afternoon and not be as easily detected by noctournal armadillos. Armadillos can be excluded from small areas with extensive damage by using fencing at least 2 feet high and with an apron buried at least 18 inches deep. Armadillos are also particularly attracted to fermenting fruit. Remove fallen fruit to avoid attracting unwelcome wildlife.