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The name "echidna" orginates from the Greek goodess Ekhidna, who had the face of a woman but the body of a serpent. The echidna may not look like either woman or serpent, but it is nonetheless just as odd looking as Ekhidna must have been.
Echidnas range from 11 to 18 inches in length and 4 to 15 pounds in weight, with populations on the Australian continent being generally larger than those on Tasmania and other islands. Hollow spines cover the entire dorsal surface, including a small tail. Fur is also present and may be even longer than the spines in some subspecies. The spines are usually yellow at the based and black towards the tip, but may be entirely yellow. The fur ranges in color from honey to a dark reddish-brown and even black.
Adaptations to the echidna's foraging habits include tubular snouts, long sticky tongues, and front paws for digging. Males have non-venomous spurs on the ankles of their hind legs and females have pouches on their undersides. The spines can be erected and limbs withdrawn for protection, similar to a hedgehog. The echidna has poor eyesight but an acute sense of smell.
Distribution and Habitat
Echidnas are found throughout mainland Australia, in southern and eastern New Guinea, and on Kangaroo Island and Tasmania. They inhabit a wide variety of habitats, including open woodlands, savanna, agricultural areas, semi-arid, and arid regions, and from sea level to above the snow line.
Echidnas feed on ants, termites, and other invertebrates. They make foraging pits by disturbing the soil when looking for food, and they prefer foraging under the canopies of large trees. They also dig into ant and termite nests with their front paws and poke their long, sticky tongues into nest crevices. Their foraging habits make separating soil from food difficult, so much of their feces consists of soil.
The mating season runs from June to August. A female may be pursued by several during this period, but will mate with only one male per season.
After a gestation period of about 23 days the female will lay a single soft-shelled egg in her pouch for incubation. The egg hatches 10-11 days later. Short-beaked echidnas on Kangaroo Island forage with the young in the pouch immediately post-hatching. After 45 to 55 days, the mother will deposit the youngster in a nursery burrow, where it will remain until weaning; the mother returns every five to ten days to nurse the young. Short-beaked echidnas in Tasmania remain in nursery burrows with the young for 25 to 35 days post-birth and then return to the burrow every three to five days to nurse. Other subspecies exhibit variations of parental care ranging between these two extremes. All short-beaked echidnas exhibit a long lactation stage lasting between 150 and 200 days, and it can take up to five years for an echidna to reach full adult size.
Echidnas can live up to 50 years in captivity, and there are reports of wild echidnas living into their 40's.
Other Habits and Behaviors
Echidnas are usually nocturnal but may be more active during the day at cooler temperatures. They are solitary except when mating. They have overlapping home ranges; their movements depend on food availability, not territoriality.
Echidnas decrease energy usage by hibernating from early autumn to late spring. During early hibernation, individuals prefer cooler soil temperatures compared with the coldest period of hibernation, at which time they will move to warmer "quarters." During hibernation there are periodic arousals from torpor. The timing of hibernation seasons varies by subspecies, geographic location, sex, and reproductive state.
This page was last updated on February 18, 2017.