Sydney's Taronga Zoo is celebrating its first successful echidna births in 30 years with three healthy babies, known as puggles, from three different mums hatching within days of each other.

Echidnas, or spiny anteaters, are notoriously difficult to breed in human care, but keepers at the zoo are pleased with the progress of the tiny trio and first-time mothers Ganyi, Spike and Pitpa.

"All three mothers are doing an amazing job and tending to their puggles as needed," said Suzie Lemon, one of the keepers.

"We have one mum, Spike, who is so attentive that she returns to feed her baby every second day."

The puggles all hatched within a short period in August and have now opened their eyes and begun to develop their characteristic spines. 

The youngest was born to Pitpa, the last puggle born at Taronga in 1987.

Echidnas, which are elusive in the wild, are one of only two Australian mammals that lay eggs, along with the platypus. 

The puggle hatches after 10 days and is carried around by its mother in a pouch-like skin fold for up to two months.

"A day in the puggle world consists of lots of sleeping," said Lemon. 

"They can be buried up to 30 centimetres (11.8 inches) deep in their burrow, so they'll just sleep and use all their energy to grow and develop."

Australia is home to a unique array of animals not found anywhere else in the world, including echidnas, koalas, dingoes, platypuses and wombats.