“I’m wondering if these fellows are vying for the idiots of the year award or the idiots of the century award,” she said.

The Queensland Department of Environment and Heritage Protection said on Monday that it was investigating the episode. It said the men could each face a fine of 15,000 Australian dollars, around $11,700, if they are found to have deliberately interfered with the crocodile trap.

The department said it condemned “in the strongest possible terms the stupid and reckless interference with crocodile traps.”

“It should go without saying that if a crocodile trap is deployed it is because there is a crocodile in the vicinity,” the department said, “so the best advice would be to leave the trap alone and exercise Crocwise behaviour.” Interfering with a trap, it said, could pose a threat to public safety and “be potentially life-threatening for the person concerned.”

The department issued a long list of crocodile-related warnings and guidelines in response to the picture and advised residents of North Queensland to assume that there are crocodiles in all of their waterways, whether they see a crocodile warning sign or not.

It also warned that people should be careful around bodies of water at night and keep their distance from crocodile traps, even when on a boat.