Seven quokkas, two yellow-footed rock-wallabies dead in Adelaide Zoo mystery

Adelaide Zoo keepers are mourning the “extremely upsetting” loss of two rock wallabies and seven female quokkas in a shocking mass death event.

Adelaide Zoo is investigating the “extremely upsetting” unexpected deaths of seven female quokkas and two yellow-footed rock wallabies.

Zoos SA on Tuesday said the animals died on the weekend of September 10, but a full pathology and toxicology report was unable to determine a cause of death.

Plant toxicity has been deemed the likely cause but further testing was still underway.

The surviving quokkas – an 11-month-old joey named Marli and three males – have been taken off exhibit.

A Zoos SA spokeswoman said the kangaroo mob and 10 remaining yellow-footed rock-wallabies were “noticeably flat” following the deaths and had been given supportive care.

She said no other animals n the zoo had shown signs of being unwell and the veterinary team was certain the deaths were an isolated incident.

Seven of Adelaide Zoo’s quokkas have died suddenly. Picture: ZoosSA

Just one 11-month-old quokka joey and three males survived. Picture: David Swift

“The loss of one animal, let alone a large group in a sudden incident such as this, is extremely upsetting, particularly for those who care for them,” the spokeswoman said.

More than 19 quokka joeys have been born at Adelaide Zoo since the introduction of its breeding program, which was launched in conjunction with Perth Zoo in 2003.

Dubbed “the world’s happiest animal”, there are just a number of scattered quokka populations in the wild off mainland WA, Rottnest Island and Bald Island, near Albany.

Adelaide Zoo’s yellow-footed rock-wallabies are also part of breeding and reintroduction programs to Aroona Sanctuary in the Flinders Rangers.