The echidna, (Tachyglossidae) also known as a spiny anteater, is Australia’s most widespread native mammal.  Significantly, along with the Platypus, the echidna is the only mammal in the world that lays eggs. In zoological terms, the platypus and echidna are monotremes, primitive mammals that lay large yolky eggs and have a common opening for the urogenital and digestive systems.

Appearance

Echidnas eat and breathe through the bald, tube-like snout. While echidna species are referred to as short or long-beaked, they actually have snouts, not beaks. They have dome-shaped bodies covered in brown fur and 5cm long (2 inch) spines similar to a hedgehog. The spines are formed from a single hair. These modified hairs range in colour from cream to black.  Echidnas have beady eyes, slits for ears, and a tiny mouth at the end of their snout. They also have a low body temperature and cannot tolerate extreme heat.  Therefore, they shelter from the midday sun and can be active both day and night.

Echidnas grow between 35 to 76 cm long and weigh 2.5 to 10 kg.  Both male and female echidnas have a belly pouch.  They have poor vision but possess an excellent sense of hearing and smell. In addition, the long spines help provide camouflage in the bush. The male echidna has the most bizarre penis in the animal kingdom. More info on that odd appendage can be found on Australian Geographic.

Diet

When hunting food, they slowly and methodically probe along the ground, searching for prey. The echidna’s long, rear-facing claws also make them excellent diggers. They primarily eat worms, termites, ants, and other insects, and, like anteaters, they have no teeth. Instead, they poke their 7-8cm snout into rotting logs and termite mounds and then use their 18cm long, sticky tongues to scoop up insects under the bark.

Species and Habitat

There are four species of echidna. The long-beaked echidna is found almost exclusively in high-altitude alpine meadows and humid mountain forests in the highlands of New Guinea.  The short-beaked echidna is found throughout Australia and New Guinea’s lowlands in various habitats, including rainforest, grassland, and desert. Sir David’s long-beaked echidna and the eastern long-beaked echidna are only found in New Guinea.  Echidnas are solitary animals apart from the mating season. However, they are not territorial.  During the winter months, they hibernate in their burrow. 

Breeding

The breeding season is from the end of June to early September. During the breeding season, it’s not unusual for a  female to be trailed by from one to ten males.  This mating train can last for up to four weeks. When the female is ready to mate, she lies relaxed and flat on her stomach.   The males that formed the ‘train’ dig a circular trench around her. Eventually, the largest male pushes the competing rivals out of this ‘mating rut’.  The male then digs more dirt out from the spot where the female’s tail is resting, he then lies on his side and, placing his tail under hers, they mate.

Echidnas are one of only five egg-laying mammals in the world that drink milk.  Apart from the four species of echidna, the only other egg-laying mammal is the duck-billed platypus. Female echidnas lay a single egg in their pouch,  which then hatches after about ten days.  At birth, the baby echidna (called a puggle)  weighs just 0.5 grams and is less than half an inch long. The puggle stays in the pouch for  4 to 5 weeks. During this time, the puggle is fed from milk, the mother secretes, and the puggle laps up. Puggles in the pouch do not have spines. The mother moves the puggle into a burrow when its spines begin to break through its skin. She will return and feed it every few days until it is about seven months old when it can leave the burrow.

Spurs

Like the male platypus, the male echidna has spurs on its hind legs.  However,  the platypus and echidna use their spurs for drastically different reasons.  In the case of the male platypuses, the spurs are a venomous weapon to help them compete against other males during the breeding season.  In contrast, the male echidnas secrete a milky substance from their spurs during breeding season as a means of scent communication with females.

Predators

Cats, dingoes and large goannas may eat the young echidnas, but adult echidnas don’t have many natural predators due to their spines.  When threatened, an echidna will curl into a ball, lodge itself into a log or rock crevice, or quickly dig a shallow excavation leaving only its sharp spines exposed.

Conservation status

In New Guinea, Sir David’s long-beaked echidna and the western long-beaked echidna are both listed as critically endangered, with populations declining.  In Australia, the eastern long-beaked echidna is listed as vulnerable, and the current population size is estimated to be around 10,000 mature echidnas, but this number is likely declining. The IUCN categorises the short-beaked echidna as a species of Least Concern. In Australia, picking up or moving one from its natural surroundings is illegal.

Echidnas are considered to be a vulnerable species due to habitat loss and disease. Conservation efforts for echidnas include protecting their natural habitats, monitoring populations, and educating the public about the importance of these animals. Additionally, organisations such as the Taronga Conservation Society Australia and the Echidna Walkabout Nature Tours offer programs to support echidna research and conservation.