Tassie tourist Suzie Dowling was heading south yesterday when she spotted a croc sunning itself on the banks of the Boyne River.
Mrs Dowling didn't stop to take a picture but said she saw the "12 to 13 foot" long croc as she and her husband drove over the Boyne River Bridge.
"If you're heading south to Bundaberg it was on the left hand side on a sand bar," Mrs Dowling said.
"It was a decent size and it definitely was a crocodile."
Mrs Dowling said her husband had been on many trips to the Top End and was well aware of what a crocodile looked like, as opposed to a log.
"I just want to let people know because there are guys on jet skis and people close to the water on the other side of the bridge," she said.
"It was just sunning itself, not moving."
Mrs Dowling had been travelling from Rockhampton today.
The Queensland National Parks and Wildlife has been notified.
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