Echidna — Spiny Anteater What is an Echidna?

Photo: Echidna walking


The echidna is an egg-laying mammal known as a monotreme. It is one of the oldest surviving examples of early mammals and shows both mammalian and bird-like characteristics. For example, even though it is a mammal that feeds its baby milk, it lays eggs like a bird or reptile. Its anatomical makeup shows the evolutionary transition of prehistoric reptile and bird-like egg layers to milk-feeding mammals.

The name Echidna is pronounced ih-KID-na. Its scientific name is Tachyglossus aculeatus (Meaning quick tongue + equipped with spines).


Echidna - Description What Do Echidnas Look Like?

Photo: Echidna spines

Echidnas are usually black or dark brown in colour. They have roundish stocky bodies covered with sharp beige and black spines. They are somewhat similar in appearance to hedgehogs.

There are two species of echidna: the short-beaked echidna, found in Australia and New Guinea and the long-beaked echidna found only in the highlands of New Guinea. The short-beaked echidna is the smaller of the species. There are five subspecies of short-beaked echidna in Australia.

An echidna measures between 30 to 45 cm in length and weighs approximately 2 to 7 kilos. Male and female echidnas are identical in appearance. A fully grown male echidna, however, is about 25% larger than a full-grown female.

Echidnas colour varies depending on their geographic location. They are light brown in the hotter northern regions but become darker in colour, with thicker fur, further south. In Tasmania, the coldest area in which they live, they are black. Two types of fur cover their bodies. A coat of short, coarse fur insulates the animals from extreme weather. While longer specialised hairs, commonly referred to as "spikes" protrude from the undercoat and cover the animal except for its face, legs, and underside. These spikes are pointed but hollow quill-like structures made up of keratin, the same material that makes up our fingernails. The echidna's tail is short, stubby, very spiny on the top and hairless underneath.

Photo: Echidna's eyes and snout

The echidna has a tiny face with small eyes. Its eyesight is poor, but it makes up for this with an excellent sense of hearing and smell. The echidna has no external ears but has funnel-like slits on either side of its head, which are well hidden beneath its fur and spines. Its slender, elongated rubbery snout, called a beak, functions as both a mouth and a nose. At the tip of this beak, on the top, are its nostrils. On the bottom is a very small mouth with toothless jaws, which can only open about 5 mm, from which the echidna sticks out a very long sticky and flexible tongue with which it catches its prey. The tongue can flick in and out at up 100 times a minute.

The echidna is one of the few land animals to have electro-receptors in its snout. These receptors enable it to locate prey by detecting the electrical signals they emit. The long-beaked echidna has as many as 40,000 electro-receptors on its beak. The short-beaked echidna, on the other hand, has only about 400 receptors.

The echidna has a distinct gait with short, stout limbs positioned on the side of its body like the platypus and reptiles. Its limbs are ideal for rapid digging. Its front feet have five flat claws forming an effective spade for digging, to burrow, dig up forest litter and to tear open termite mounds and rotting logs. Its hind feet point backwards, and help it push soil away while the animal is burrowing. The second claw on each hind foot is extra-long and also helps in grooming, where it is used to comb and scratch out dirt and bugs from its fur and spines.

25 Echidna Facts

  1. The echidna is an egg-laying mammal.
  2. This is very unusual because mammals usually don't lay eggs–except for the platypus, its distant cousin.
  3. The echidna is an example of what early mammals may have been like–egg-layers.
  4. Echidnas live throughout Australia.
  5. They have roundish bodies covered with sharp beige and black spines.
  6. They are somewhat similar in appearance to hedgehogs.
  7. There are only two species of echidna: the short-beaked echidna and the long-beaked echidna.
  8. An echidna is 30-45cm in length and weighs 2-7kg.
  9. Males and females are similar in appearance.
  10. But the female is about 25% larger.
  11. The echidna has very poor eyesight.
  12. But it makes up for this with an excellent sense of hearing and smell.
  13. The echidna has no external ears but has funnel-like slits on either side of its head.
  14. It has a slender, elongated rubbery snout called a beak.
  15. From which it sticks out a long sticky tongue to catch its prey.
  16. Its tongue can flick in and out up 100 times a minute.
  17. The echidna’s diet consists of termites and ants.
  18. The echidna has no stomach. Its gullet connects directly to its intestine.
  19. Echidnas have a body temperature of 5-8°C lower than other mammals.
  20. It has only one rear opening called a cloaca. Other mammals have two.
  21. Echidnas have a small neocortex, the most recent part of the brain to evolve.
  22. The female echidna lays a small, leathery egg and places it in her pouch where the egg hatches.
  23. She has no nipples or teats like other mammals.
  24. Instead, it oozes milk through its skin and the baby laps it up.
  25. The lifespan of an echidna is 16 years.

 


Echidna Adaptations They are Unusual Animals Indeed

Besides being an egg-laying mammal which indeed is unusual, the echidna also has several other characteristics, which makes it quite unique.

The echidna has no stomach

Its gullet connects directly to its intestine. There’s no sac, like in most other animals, in the middle that secretes powerful acids and digestive enzymes.

Lower Body Temperature

Echidnas have a body temperature of between 31-32°C, which is between 5 to 8°C lower than other mammals. For example, a rabbit's body temperature is 38–40°C.

Echidnas have only One Rear Opening

The echidna has only one opening at the end of its body called a cloaca. This all-in-one opening is the exit of a common chamber into which the intestinal, genital, and urinary tracts discharge. This is a common characteristic amongst birds and reptiles but very rarely found in mammals. In other mammals, these are separated into two openings, namely the rectum/anus and reproductive tracts such as the vagina and penis.

Echidnas Hibernate

The echidna is one of the very few Australian animals that hibernate. (The others are four species of possum and a few bats). It is also the largest of these hibernating Australian animals. Hibernation is an extended period of deep sleep or inactivity that allows an animal to survive extreme environmental conditions such as the coldness of winter. In this state of near suspended animation the animal’s heart rate, breathing and body temperature drops significantly thereby conserving energy. During hibernation, an echidna’s body temperature falls to very close to that of the temperature of the soil around it. This can be as low as 4.7°C, with a reduced heart rate of just 4 beats per minute. Hibernation usually starts in late summer and ends in June-July. During hibernation echidnas regularly rewarm themselves and may move to another location. They seem to do this to find the coldest rest spot when it's hotter and the warmest rest spot when it gets cooler, thereby maintaining an optimal hibernation body temperature. In this state, the echidna's metabolic rate is around 30% of that of equivalent sized placental mammals, making it the lowest energy-consuming mammal in the world. In cold areas, echidnas hibernate for 6-28 weeks. Males go into hibernation earlier than females with young. Yearlings that don't breed, stay longer in hibernation. The echidna uses hibernation as a hardy tactic to deal with the extreme heat of bushfires too.

The Echidna has a Small Neocortex

The echidna's neocortex makes up less than half its brain. In a human, it is about 76%. The neocortex is the most recent part of the brain to evolve. This too, highlights the fact that these are the last of a prehistoric group of animals pre-dating modern mammals.

Echidnas have Spurs

The echidna is born with a spur on each of its hind legs. These soon disappear in the female. These spurs may once have produced venom and have served a defensive purpose (like the poisonous spurs of the platypus). The spurs of the echidna today seem to serve only a communication function. Recent research suggests that the echidna secretes a waxy substance from these spurs which it uses to mark its territory to indicate its readiness to mate to females, or as a signal to other males to keep away.


Echidna - Habitat Where Do Echidnas Live?

Photo: Echidna in its habitat

Echidnas live throughout Australia in almost all habitats, from snow-covered mountains to deserts and even urban areas. They are shy well-camouflaged animals that you would seldom encounter. They are usually found among rocks, in hollow logs, and in holes among tree roots or rummaging through leaf litter or sometimes in wombat or rabbit burrows.

For most of the year echidnas are solitary, territorial animals roaming over a large territory that often overlaps with the territories of other echidnas. While there is an adequate food supply, echidnas will generally remain in a fixed location.

Echidnas tend to avoid temperature extremes. In temperate climates, echidnas are most often seen during the early morning and in the late afternoon. In hot arid environments, echidnas forage during the night and shelter in rock crevices, burrows or caves during the hotter parts of the day. This is because echidnas do not have sweat glands, nor do they pant to lose body heat.


Echidna - Diet What do Echidnas Eat?

The echidna’s diet consists mainly of termites and ants. It uses its nostrils and electro-receptors on the tip of its beak to locate its prey, which is usually hidden within a termite mound, anthill, a rotting log or under leaf litter. Once it has detected its prey, the echidna uses its powerful claws to tear open the mound and nests. It then flicks its 18cm long sticky tongue in and out to lap up its prey. The echidna has no teeth. So it uses hard keratin pads at the base of its tongue to push food up against the roof of its mouth and grinds its meal into a paste before swallowing. They avoid termites and ants that bite, sting or have chemical defences.

The echidna gets most of the water it requires from its diet. This is sometimes supplemented by drinking water or by licking morning dew from plants and grasses.

Like most Australian animals, the echidna's feeding habits are governed by the climate. In very hot weather it is nocturnal, only feeding at night. In cooler climates the echidna is diurnal, foraging in the mornings and evening.

Echidna Feeding Video


Echidna - Reproduction & Life Cycle Mating, Egg Laying, No Nipples for Milk

Photo: Echidna egg

Echidnas are promiscuous. They mate with as many partners as possible. They mate by lying on their sides with their spineless undersides facing each other, so their spiky spines don't get in the way. The male penis located inside its cloaca is extended out and inserted into the female cloaca for impregnation.

After fertilization, the female begins to develop a temporary pouch which is essential a depression in her abdomen covered by two overlapping flaps of skin. Approximately 16 days after fertilization, she lays a single leathery egg, roughly the size of a small grape (13–16 mm), into her pouch. Nobody knows for certain how she does this. Some suggest that she collects the egg as it comes out of her cloaca and deposits it into her pouch. Another more likely scenario is that she curls up into a shape like the letter “C” and deposits the egg from her cloaca directly into her pouch. She then incubates the egg in her pouch for 10 days.

Photo: Echidna baby’s eye-tooth

On about the tenth day the young echidna, referred to as a puggle, uses its eye-tooth (another example of its reptilian ancestry) to tear through its leathery shell and exists into the pouch. At this stage, it has well-developed forelimbs and is about the size of a small jelly bean. The puggle uses its forelimbs to hold onto fur in its mother's pouch.

Photo: Echidna baby called a puggle

The mother echidna has no nipples or teats like other mammals. Instead, it oozes milk through its skin from specialised milk patches. The puggle nuzzles up against these patches, which encourages them to secrete milk which the puggle licks up rapidly.

The baby puggle stays in its mother's pouch for about 3 months. During this time, the female may remove the puggle from its pouch and leave it in a special nursery burrow while she goes out to forage for food. Once the puggle's spines have begun to develop its mothers, no doubt finding it uncomfortable encourages its offspring to spend more and more of its time outside the pouch. When the puggle is about 200 days old, the mother will feed it one last time, dig out its nursery burrow opening and leave the young puggle to fend for itself. She will not return to the burrow again.

The average lifespan of an echidna in the wild is estimated to be around 16 years. Some are known to have lived to up-to 45 years of age. Their longevity is attributed to their rather "laid back" lifestyle and low metabolic rate.

Echidna Love train

Video: Watch an echidna love train

Echidnas are solitary animals. The only time they socialise is between June and September when female echidnas are receptive to advances from males. The typical echidna mating ritual is one of pursuit. Up to 11 males echidnas form a line, sometimes referred to as a “love train”, and follow a female around for extended periods and try to mate with her. Usually, the male who endured the longest and stuck closest to her is the successful suitor.


Echidna - Swimming Can Echidnas Swim?

Echidnas are good swimmers. They are known to visit their favourite watering-holes for an occasional dip. Unlike most land animals, the echidna swims with its head underwater, only lifting its beak above the waterline when it needs to take a breath. Like most quadrupeds (four-legged animals), the echidna uses a dog paddling swimming stroke.

Echidna Swimming


Echidna's Defences How the Echidna Protects Itself from Predators

The echidna's speckled brown body is its first defence against predators. It will stay motionless for long periods and try to blend into its environment.

If it is confronted while on a hard surface, which it cannot dig into, the echidna may try to waddle away at full speed. Unfortunately, it is not a very fast runner.

Photo: Echidna curled up in a ball with spines exposed

Photo: Echidna burying itself in the ground

Its next strategy is the curl up into a spiky ball, protecting its underbelly and head and exposing only its spines to its assailant. Very few predators would attempt to attack the echidna in this pose.

The echidna's favourite defensive tactic is to use its powerful claws to dig itself into the ground until it is completely covered by soil or firmly embedded into the soil so that it is difficult for any predator to dislodge it. It may also try to wedge itself under a rock or log while exposing its spiky spines, making it nearly impossible for an assailant to pull it out.


How Echidnas Survive Bushfires Echidna's Unique Bushfire Survival Tactics

Photo: Echidna burying itself against a bushfire


Photo: Echidna walking in bushfire ravaged land

Australian bushfires are terrifying events. Raging fires with flames as high as four-story building tear through tinder-dry vegetation at breakneck speeds, incinerating almost everything in its path and leaving a charred desolate landscape behind.

Many people have noticed that after a bushfire, the only animals that seem unaffected by the catastrophe are echidnas. They have been seen frequently roaming about the burnt-out landscape seemingly untouched. So how do they do it? What survival tricks do they use?

The echidna survives by digging itself below the surface of the ground. The layer of earth above it protecting it from the scorching flames and heat overhead. It then hibernates, lowering its metabolic rate drastically thereby reducing its oxygen requirement and allowing it to breathe the toxic oxygen-starved and carbon dioxide saturated environment of its underground shelter. Following the devastation of a bushfire, the echidna emerges from the safety of its underground shelter. Because food is scarce after a bushfire, the echidna compensates by dropping its body temperature down by as much as 20 °C, slowing its heartbeat and decreasing its metabolism and goes into frequent states of torpor (mini hibernations) for as long as three weeks enabling it to conserve energy and live through the hard times.


Echidna - Predators & Threats What Treats Do Echidnas Face?

Photo: Echidna crossing a main road

The only native predator of adult echidnas is the Tasmanian Devil. Baby echidnas sometimes fall victim to goannas — native monitor lizards who tear open their nursery burrow and capture spineless little puggles. Snakes too venture into nursery burrows and attack the young puggles. Several introduced animals such as dingoes, foxes, feral cats, and dogs are known to attack echidnas. Fortunately, the echidna’s spiky defences offer it good protection and these attacks are rarely successful.

Aborigines have been hunting echidnas since they arrived in Australia about 50,000 years ago. They have, however, had little impact on the overall survival of the echidna population. Since the arrival of European settlers in 1778, humans have had a larger impact on the echidna population as a result of land clearing and forest felling. The echidnas, however, are very versatile and adaptable animals and don't seem to have been seriously affected by these activities either.

Australian bushfires are the largest single threat to an echidna. The echidna is too slow to run away. So instead of fleeing it stays put and adapts a rather bizarre survival tactic.


Echidna - Conservation Status Is the echidna Endangered?

The echidna is quite common and not considered threatened. It is protected by Australian law.


How Did the Echidna Get its Name? The Echidna is Named After a Greek Goddess

The name Echidna is derived from the Greek name Ekhidna. Because the echidna appeared to be half reptile and half mammal, in 1802 the British anatomist Everard Home named this unusual animal after the Greek goddess Ekhidna (meaning "she viper") who was half-snake and half-woman.


Echidna and the Mutiny on the Bounty How are They Related?

Photo: HMS Bounty

The first European to describe the echidna was, in fact, none other than William Bligh, the captain of the sailing ship the HMS Bounty of Mutiny on the Bounty fame. The Bounty was on its way to Tahiti in 1792 when it stopped at Adventure Bay in Tasmania. There Bligh reported that the animal had a bill like a duck and a thick brown coat of hair with quills. A member of the crew shot an echidna and later roasted it, reporting that it had a "delicious flavour".


An Excerpt from the Original TrishansOz Page

(Excerpt from the original TrishansOz page written in 1997 when Trishan was 11 years old.)

An echidna is about 50 cm long, and it is dome-shaped. It has short sharp spikes covering its body (like a porcupine). It has a short pointy snout and a sticky tongue with which it catches ants and termites. It has no teeth. The echidna has very sharp claws too and can burrow underground very quickly. An echidna has short stubby feet and waddles when it walks.

When it gets frightened, it raises its spikes to defend itself and tries to dig itself into the ground.

Echidnas adapt their activity according to the climate they are in. In hotter climates, they are nocturnal, coming out only during the cooler hours of the night. In cooler climates, they more diurnal, coming out during the day to forage for food.

You can see how the echidna is trying to hide in the photograph.

My dog Sage once tried to catch an Echidna and hurt his tongue.