Three vessels are currently searching the waters on the eastern side of the island, also known as Minjerribah, while drones are flying above, a Department of Environment and Science spokesman told AAP.
"The Queensland Parks and Wildlife Service has flown two experienced crocodile management wildlife officers from North Queensland to assist in the investigation,"
- Department of Environment and Science spokesman
Residents and visitors are urged to continuing avoiding the area while investigations proceed, while people have been asked to refrain from flying private drones.
Bond University Marine Scientist Dr Daryl McPhee said if the crocodile was found, it would be "exceptionally rare" and “one-in-one-hundred-year event".
"The person who reported it ... is highly credible. He's a local traditional owner but also somebody who's spent a lot of time on the water, so I certainly put some credibility in what he's seen," he told AAP on Wednesday.
"It is feasible but obviously exceptionally rare for a crocodile to be this far south."
The crocodile, if confirmed, has travelled more than 400 kilometres south if its habitat range.
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