Specialist wildlife officers with advanced skills in crocodile management have been flown to the island, also known as Minjerribah, off Brisbane, to join the search for the reptile which has so far avoided detection since it was spotted and reported to rangers from the Quandamooka Yoolooburrabee Aboriginal Corporation on January 18.

Officers in three boats are currently searching waters on the eastern side of the island, while a vessel-based spotlight survey in conjunction with aerial assessments has failed to reveal any evidence of the animal.

Crocodile experts say the presence of the reptile in such far southern waters would be “extremely rare”, but not outside the realms of possibility and maintain the source who reported the sighting as credible.

Typical crocodile habitat begins at the Boyne River south of Gladstone, and extends northward, up the east coast and across far north Queensland.

A key finding from the department’s Queensland Estuarine Crocodile Monitoring Program 2016–2019 found the distribution of crocodiles in Queensland has not changed over time, and found no evidence of a southward expansion of their range.

This is despite several crocodiles having been spotted and trapped in the Mary River, about 100 kilometres north of Noosa and 250 kilometres south of their normal range in recent years, a development blamed on global heating from climate change.

In 1905, a crocodile was shot and killed in the Logan River by locals in Beaudesert, although the three metre animal’s origins may have been traced to an irresponsible owner in Brisbane who was keeping it as an exotic pet.

And a female crocodile nicknamed Hector once lived in Wilsons River in Lismore, NSW before it curiously vanished in the 1974 floods.

A Department of Environment and Science (DES) spokesperson said the sighting near Myora Springs, just north of Dunwich, was still classified as ‘unconfirmed’ but all reports of a potentially dangerous animal were taken seriously and investigated thoroughly.

They said crocodile warning signs would be installed at boat ramps during the investigation.

Visitors and residents on Minjerribah are being urged to stay away from Myora Springs for safety reasons, and to allow rangers to complete their investigation.

The natural ecosystem is listed as a “lesser-known gem” on the Visit Brisbane tourist page, which promotes its natural beauty as the place to “explore and enjoy peacefully”.

If the reptile is confirmed to be present on Minjerribah, regardless of size, it will be targeted for removal under the Queensland crocodile management plan.