The Echidna (aboriginal, Nynghan) is one of two egg-laying mammals (the echidna and platypus) that inhabit Australia and Papua New Guinea.

Three species of the long-nosed echidna live in New Guinea- the short-nosed species (Tachyglossus aculeatus) is widely distributed in Australia; it occurs in almost all Australian environments, including the snow in the Australian Alps and Outback deserts. In Roleystone where there are plenty of ants and termites they can be seen on a rare occasion, at dusk or at night, since they don't like the heat.. They are normally recluse and shy; their home territory needs to be removed from habitation and they don't cope well with roads and vehicles. For instance, twice in one year we (Don Hill and I) saw one on the Echidna Walktrail, 100m or so along and below the climbing rock. On our properties on Wymond Rd., one comes through every few years.

When disturbed, they appear to become part of a balga or zamia or whatever, a spiny ball which protects their underbelly. Normally, however, they are happy to carry on with their slow, ambling gate, like a little bull dozer. Walking in the bush, I have seen them about to cross the trail; I keep walking, and they cross just in front of me, steadly without deviation in their path. Indeed, one entered the open metal door of my shed while my wife and I were inside. It just kept going, though we tried to turn it around or stop it. It could push your foot out of the way! Eventually I moved the metal door and piled some heavy metal pieces in its way. It turned, and went its way. We did see it several times in the next week or so.

An echidna has a extended, combination nose with a small mouth, sensitive to smells, that also detects electrical signals. They dig the ants out with their powerful front and rear claws and poke ants out of their holes with their rapidly moving 15 cm tongue, covered with a layer of sticky mucous, the name Tachyglossus means 'fast tongue'. Their jaws are narrow and food is crushed between hard pads in the roof of the mouth and on the back of the tongue. The ‘poke-holes' commonly made in their  searches consist of a small centre hole of shout size and a larger part where they have moved earth with their front claws. See http://www.dpiw.tas.gov.au/inter.nsf/WebPages/BHAN-5357K5?open

The picture shows their soft, featureless underbelly. Except for special folds that form to hold the egg and young, there is no apparent special feature in male or female, except the male has a special part on his body, which can sprinkle a poison.  

Echidnas lay soft-shelled eggs into the specially formed folds on their belly. In 10 days or so, the eggs hatch and the ‘jellybean' fetus-like baby lives by sucking up milk exuded from two featureless sweat glands. The baby ‘blob' is called a ‘puggle'. When the puggle is 7 weeks old, it becomes too spiny and the mother puts it into a special burrow for the next 5 months; the mother returns every 5-10 days for feeding. At 7 months a wee ‘spiny anteater' is fully formed, and the mother just leaves it to fend for itself.

Echidnas live to be about 45 years old, have lower body temperature (~33C) and may undertake a special type of hibernation. They like a lot of space, do not have exclusive ranges and can range over 100s of hectares, perhaps 80 km or more. They don't follow regular paths and may have 5 or more burrows. Land clearing, fragmentation by roads, clearing and fences have made it difficult for them.

The Scribbly Gum ABC web site has great detail, and describes the matting process: http://www.abc.net.au/science/scribblygum/June2000/
http://www.abc.net.au/science/scribblygum/June2000/gallery.htm

In winter males court females by queuing up, nose to tail, to form long trains; this can go on for 6 weeks, before matting. The males make some advances by nudging the females tail or side; when she is ready, she parks herself near a bush and the males start digging by her side, eventually digging a ring right around the bush; this rut ends when only one male remains under the female; he turns on his side and they mate,
cloaca to cloaca. Breeding only happens after they are 5-7 years old and then every 3-7 years.

As mentioned, we had trouble turning an echidna away from our shed. One friend relates having collected one from an unfortunate situation, and placing it in the boot of a car. Having extracted it from danger, he couldn't get the echidna out--it had thoroughly attached itself deep in his boot! He took it home and simply left the boot open-it had gone the next morning. I am told that a way to manage (herd) echidnas is to tickle their soft, furry bellies. They then roll over on the opposite side and, with some tricky ‘tickling', get reorganised and at least going in the right direction.

By the way, they don't have barbs on their spines, which are modified hairs, they don't have poison barbs either; though they have hairs in-between the spines. Echidna in Greek legend was a ‘Mother of All Monsters', a quite inappropriate name for a lovely, mild and shy critter, better to use the aboriginal word ‘Nynghan'. Unfortunately, the aboriginals believe they are good eating!