Queensland Parks and Wildlife is investigating a saltwater crocodile sighting after a group of kayakers reported coming within metres of the animal on Minjerribah (North Stradbroke Island) off Brisbane.
Rangers from the Quandamooka Yoolooburrabee Aboriginal Corporation received a report of a 3 metre crocodile at Myora Springs, just north of the town of Dunwich on Wednesday morning, the Department of Environment and Science said.
Straddie Adventures owner Mark Jones said he spotted it on a kayak tour with a family of nine along the edge of the mangroves.
"We were only probably 10 to 15 metres away, so it was close enough to see the front of it, the head, eye area and the tail," Mr Jones said.
He said he first thought it was a log but soon realised it was a "3- to 4-metre" crocodile.
"The 'log' then sunk in the water," he said.
"And then it raised up again, so we all confirmed it was a croc."
'I carry my spear on my kayak'
But Mr Jones said he was not worried.
"We just paddled away from it because it started to head north, and my tour goes south," he said.
"My customers, I just told them to go ahead of me, and I'd follow from the back and just watch to see if it comes anywhere in because I always carry a spear on my kayak."
Mr Jones said he reported the sighting to the authorities once back onshore.
He believed the crocodile was "out chasing a feed."
"I know there's plenty of Stingray, shovelnose and fish around that area," Mr Jones.
Mr Jones said tomorrow's tour might be in a boat rather than on a kayak.
Croc possibly 'drifted down with some currents'
Bond University Associate Professor of Environmental Science Dr Daryl McPhee said he believes the report is credible.
"The sighting has come from a traditional owner who spends a lot of time on the water," he said.
"I think it's just drifted down with some currents, and it's found a pretty good habitat.
"It's a good quality mangrove there, there is a fair bit of fish and there's a nice freshwater stream."
Dr McPhee said he believes the crocodile has not recently moved to the bay.
"It's unlikely that it's just come down yesterday or this morning, may well have been there for a period of time," he said.
But said it was still very rare for the area.
"It is not common at all, so the last really recorded crocodile in the area was in the Logan River in 1905," he said.
Dr McPhee said it is too early to suggest crocodiles have begun to migrate further south, and expects the rest of the population to remain in the core areas around Gladstone to north of Cape York.
Croc-spotting at night
Searches will continue through Wednesday night using spotlights.
Director of Southern Wildlife Threatened Species Operation Geoff Lundie-Jenkins said crocodiles "have a very distinctive eye-shine".
"It's often easy to actually sight them in open waters at night using spotlights," he said.
Mr Lundie-Jenkins said the crocodile could be confused and disorientated.
"The tendency with these types of crocodiles that are well outside their normal range, is that they are normally larger, older crocs that have been displaced either by weather events or flooding or to aggression in their own home range," he said.
Residents urged to stay away
Residents have been urged to "steer clear" while rangers search the area with boats and drones.
Crocodile warning signs have also been installed at boat ramps.
The department said "any crocodile confirmed to be present on Minjerribah (Stradbroke Island), regardless of size, is targeted for removal from the wild."
