Elephants licked iceblocks, lemurs ate apples, and the koalas were given a special serving of their customary eucalypt leaf, a zoo spokesman said.

In the giraffe enclosure, olive boughs were shaped to form the figure "100" and served as breakfast, consumed with relish by the giraffes before a backdrop of the harbor with the city and its famous bridge.

One of Sydney's main tourist attractions, Taronga Zoo opened in 1916, when Australia was at war in Europe.

Its "bar-less" enclosures were inspired by Hamburg Zoo and it was stocked with a menagerie of 228 mammals, 552 birds and 64 reptiles which crossed Sydney Harbour by barge from an earlier zoo.

"A hundred years ago Taronga was primarily a place of entertainment, today it is leading world cutting-edge research and education for wildlife," New South Wales state environment minister Mark Speakman said at the zoo.

The celebrations were launched by a Fiordland Crested Penguin called Munro, who stood by while keepers sang "Happy Birthday", some dressed in historic uniforms.

Each year, about 1.4 million people visit the zoo and it is now home to more than 4,000 animals.

REUTERS