Authorities in Western Australia are investigating the deaths of five quokkas that were found stuffed head-first into tree protectors on Rottnest Island on Monday.



The animals were found by Peter Basford, who told Seven News in Perth that he was visiting the island and found the animals near the camping ground.

“I saw a couple of them with their heads sticking out the bottom, the heads facing up … I can’t think of anything more gruesome,” he said.

Basford, who was described as a regular visitor to Rottnest, said the island was “supposed to be a paradise”.

A spokeswoman from the WA Department of Parks and Wildlife told Guardian Australia that six quokkas had been found dead – five stuffed into tree protectors and another one lying nearby. They are believed to have been there for up to a week.

She said the animals had “clearly been killed” but it would be inappropriate to speculate on how they were killed until the investigation was completed. The department has conducted autopsies and Rottnest Island police tweeted a plea for information about the incident on Wednesday.

Taking protected fauna carries a fine of up to $10,000 under the Wildlife Conservation Act.

Quokkas are listed as a vulnerable species. Mainland colonies were all but wiped out after European settlement, thanks to a combination of foxes and disease.

The biggest and most stable population is on Rottnest Island, a holiday island about 30km off the coast of Perth, and quokkas there have become very comfortable around humans.

It’s not unusual to see visitors stop their bicycles to let quokkas past, and while it’s illegal to feed them, they do hang around dining areas looking for a snack.

The Rottnest Island Authority chief executive, Paolo Amaranti, who said he was wearing a quokka lapel pin, told Guardian Australia that quokkas were a major tourism drawcard.

Amaranti said he had worked on the island for 10 years and never heard of quokkas being “deliberately and maliciously” killed before.

“For quokkas to be deliberately killed is just a disgrace,” he said. “That’s the defenceless quokka who will want to come up to anyone. They’re not fearful of human beings.”