Myrmecophaga tridactyla

Geographic Range

Giant anteaters are found in Central and South America, from southern Belize and Guatemala to northern Argentina.

• Biogeographic Regions
• neotropical neotropical

Habitat

Giant anteaters use a variety of habitats, including swamp, forests, and grasslands. They choose secluded, covered areas for sleeping. Giant anteaters can be found in both rural and densely populated areas.

• Habitat Regions
• tropical tropical
• terrestrial terrestrial

• Terrestrial Biomes
• savanna or grassland savanna or grassland

Physical Description

Giant anteaters are quite distinctive morphologically, they are the largest of the anteater species. The snout is long (up to 45 cm in length) and the skull is streamlined with small eyes and ears. The tail is large and bushy and is nearly as long as the body. Head and body length measures 1,000 to 1,200 mm and tail length 650 to 900 mm. Weight ranges from 18 to 39 kg. Giant anteaters have fur that is thick and coarse and longer towards the tail. Their coat is brown with black and white stripes on the shoulders and a crest of hair along the middle of the back. The forelegs are white with black bands at the toes. Their hindfeet have 5 short claws, while their forefeet have 5 claws with the inner 3 being very long and sharp. They walk on the wrists of their forefeet, with these large claws curled out of the way. Giant anteaters have no teeth. The tongue can be extended 610 mm outside of the mouth and has spine-like protrusions.

• Other Physical Features
• endothermic endothermic
• homoiothermic
• bilateral symmetry bilateral symmetry

• Sexual Dimorphism
• sexes alike

Reproduction

The mating system of M. tridactyla is not known. Reproductive behavior is primarily observed in captivity. The male stands over the female who lays on her side during copulation.

Gestation is approximately 190 days, after which females give birth to a single young which weighs about 1.3 kg. Females give birth standing up and immediately the young anteater climbs onto her back. Young are born with a full coat of hair and adult-like markings. Breeding occurs year-round in captivity and the wild, though seasonal breeding times have been reported in portions of their range. Inter-birth intervals can be as low as 9 months. Sexual maturity is reached between 2.5 and 4 years. The mammary glands are lateral to the 'armpits' on the chest.

• Key Reproductive Features
• iteroparous iteroparous
• seasonal breeding seasonal breeding
• year-round breeding year-round breeding
• gonochoric/gonochoristic/dioecious (sexes separate)
• sexual sexual
• viviparous viviparous

Young are born with a full coat of hair and adult markings and are capable of clinging to their mother at birth. A mother will carry the baby on her back until it is almost half her size, about 6 to 9 months. Young suckle for 2 to 6 months. They become independent after about 2 years, or when the mother becomes pregnant again, which may be sooner.

• Parental Investment
• precocial precocial
• female parental care female parental care

Lifespan/Longevity

Giant anteaters have been known to live up to 25 years and 10 months in captivity. Their longevity in the wild is unknown.

Behavior

Giant anteaters are usually solitary, except for mother-young pairs, only coming together for brief periods for courtship and agonistic encounters. They may have large, defined home ranges up to 9,000 ha in area, but they also wander extensively. When giant anteaters encounter each other in the wild they often simply ignore each other or run away, though agonistic encounters do also occur. Usually diurnal, giant anteaters will become nocturnal in areas of high human density or during certain kinds of weather. They are terrestrial but are good swimmers as well and, though they don't often climb in the wild, they are reported to be skilled at climbing out of enclosures in captivity. Sleeping occurs in abandoned burrows, dense vegetation, or depressions in the ground. Although they have the ability to dig well, they do not construct burrows. When fights occur individuals rear into a bipedal stance using the tail to balance and the forelimbs to fight. They shuffle while walking and move slowly but are capable of running quickly if necessary. Their weight is born on the knuckles and wrist to protect the claws.

• Key Behaviors
• terricolous
• diurnal diurnal
• motile motile
• nomadic nomadic
• solitary solitary

Home Range

Home ranges may be as big as 9,000 hectares in area.

Communication and Perception

Most communication occurs between young and their mothers or during fighting. It consists of snorts, sniffs, and hisses, as well as roaring during fights. Sight and hearing are diminished. Smell is highly developed-40 times that of humans.

• Communication Channels
• tactile tactile
• acoustic acoustic
• chemical chemical

• Perception Channels
• visual visual
• tactile tactile
• acoustic acoustic
• chemical chemical

Food Habits

Giant anteaters eat ants, termites, and soft-bodied grubs. Using the long, sharp claws on their forelimbs, they open insect colonies and tree trunks. They then use the tongue to collect the eggs, larvae, and adult insects. The salivary glands secrete sticky saliva during feeding that coats the tongue. They only stay at one ant colony for a short period of time because soldier ants arrive but giant anteaters can consume a few thousand insects in minutes. The tongue is attached to the sternum and moves very quickly, flicking 150 times per minute. They may sometimes eat fruit.

• Primary Diet
• carnivore carnivore
  • insectivore insectivore

• Animal Foods
• insects

• Plant Foods
• fruit

Predation

Giant anteaters can use their immense front claws to defend themselves from predators, though their typical response to threat is to run away. Their size makes them invulnerable to all but the largest of predators, jaguars and pumas primarily. They are often killed by humans, either intentionally through hunting or unintentionally through collisions with cars.

Ecosystem Roles

Giant anteaters, through their diet, have an enormous impact on local insect communities.

Economic Importance for Humans: Positive

Giant anteaters are hunted for food, fur, and sport. They are also valuable for the criical ecosystem roles they play.

• Positive Impacts
• body parts are source of valuable material
• controls pest population

Economic Importance for Humans: Negative

Giant anteaters are increasingly killed in car accidents.

Conservation Status

Habitat destruction is the primary threat to giant anteaters. They are listed as Appendix II by the Convention on International Trade in Endangered Species (CITES). Appendix II is defined as a species not necessarily threatened to extinction but one that should be controlled in trade to avoid overuse. They are listed as vulnerable by the International Union for Conservation of Nature and Natural Resources (IUCN). 'Vulnerable' is defined as an estimated population reduction of 20% in the next 10 years.

Additional Links

Encyclopedia of Life

Contributors

Amy Woltanski (author), Michigan State University, Barbara Lundrigan (editor), Michigan State University.

References

Anderson, S. 1967. Recent Mammals of the World . New York: The Ronald Press Company.

Jones, M. 1982. Longevity of captive mammals. Zool. Garten , 52: 113-128.

Naples, V. 1999. Morphology, evolution, and function of feeding in the giant anteater. Journal of Zoology-London , 249: 19-41.

Nowak, R. 1999. Walker's Mammals of the World, Volume I . Baltimore and London: The Johns Hopkins University Press.

Redford, K., J. Eisenberg. 1992. Mammals of the Neotropics . Chicago, IL: University of Chicago Press.

Shaw, , Machado-Neto, Carter. 1987. Behavior of free-living giant anteaters. Biotropica , 19(3): 255-259.

CITES Secretariat. 2003. "Convention on International Trade in Endangered Species of Wild Flora and Fauna" (On-line ). Accessed 02/02/03 at http://www.cites.org .

IUCN. 1997. "International Union for Conservation of Nature and Natural Resources" (On-line ). Accessed 02/02/03 at http://www.redlist.org .

Rain Forest Conservation Fund. 2001. "Rainforest Conservation Fund: Species Data for Giant Anteater" (On-line ). Accessed 02/02/03 at http://www.rainforestconservation.org/data_sheets/mammals/anteater.html .