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Sydney's Taronga Zoo has been reprimanded by animal rights activists for letting an Asian elephant fall pregnant even though she is only nine years old.

The zoo, famed for its views over Sydney Harbour Bridge and the Opera House, proudly announced today that Thong Dee was five months into a 22-month pregnancy and should become the first captive elephant in Australia to give birth. It even released ultrasound images to confirm what it called an "historic event".

But Erica Martin, who heads the Asia Pacific office of the International Fund for Animal Welfare, said that allowing such a young elephant to get pregnant was the equivalent of allowing your 12-year-old daughter to become pregnant”.

“It is completely irresponsible,” she said.

The ultrasound images identify a 10cm foetus with the beginnings of a spine, front and hind legs, although it is too early to determine whether it is male or female.

Thong Dee was a part of a group of eight Asian elephants imported from Thailand in November 2006.

Animal rights groups said today that there was little conservation benefit in Thong Dee’s pregnancy and that the young elephant faced health risks.

“We know that calves born in zoos have double the mortality rate in the wild, and this pregnancy will put both mother and calf at great risk,” said Bidda Jones, chief scientist of the Australian RSPCA. “Stillbirth, infanticide and rejection of calves are the main causes of infant mortality and Thong Dee’s age and lack of maternal and social experience make this pregnancy very risky."

The zoo says that its four female Asian elephants have all been assessed by reproductive specialists as eligible for breeding and points out that the early Asian Elephant pregnancy in a European zoo was five and a half years.

Mr Cooper said: “The well-being of all animals in our care is of paramount importance and our breeding programmes are carefully managed to exacting standards that ensure our specialist staff employ the latest advice and scientific research."

Asian elephants are smaller than their African cousins and are listed as endangered. They live for about 80 years in the wild and about 60 in captivity.

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