Australia's National Parks and Wildlife Service is currently searching for a suspected platypus killer following the discovery of three carcasses in the Aubury botanic gardens over the last five weeks.

All three animals were reported to be of a healthy body weight, suggesting they had been deliberately caught in a manmade trap.

Two of the bodies appeared to were fully decapitated - albeit with some difficulty - with a sharp object.

The first platypus was found in early March by a gardener, while the other two were found by members of the public, most recently on Wednesday.

A spokeswoman for the botanic gardens said the incident is being treated as a case of animal cruelty.

"These animals appear to have been deliberately killed in a despicable act of cruelty to one of Australia's most loved animals."

Authorities are asking visitors in the area to be mindful of any suspicious activity.

A reward of 5,000 Australian dollars (3,500 euros) is currently being offered by the Humane Society International Australia for any information leading to arrests.

Harming native animals in New South Wales carries a maximum penalty of six months jail and/or a fine up to 11,000 Australian dollars.

Platypus are difficult to spot in the wild

Killer 'wanted to be noticed'

Hazel Cook, the secretary of the Wildlife Information Rescue and Education Service in Murray River, told local newspaper "The Border Mail" that the perpetrator appeared to want the dead animals to be found.

The closest platypus habitat is nearby Murray River, about half a kilometer away from the botanic gardens, meaning the carcasses had been purposely transported to and discarded in a busy public area.

"It's just sad," said Cook, "I think they need some help."

"We have no idea why anyone would do that, especially to something as gentle as a platypus. Even the fact that someone caught three of them is concerning."

The platypus, an unusual mammal with a furry body and a beak like a duck, is well-known for its elusive nature, and is rarely spotted in the wild.

Protected species

While the platypus is not yet considered endangered, it is classified as a protected species under the National Parks and Wildlife Act.

However, a two-year long study is currently aiming to assess the current status of the beaked mammal, with researchers growing increasingly concerned by a number of threats such as riverbank erosion and foxes, an invasive species.

The platypus is native to eastern Australia, including Tasmania, and is extinct in South Australia.

im/sad (AFP)