Around 40 crocodiles have set up shop at Cahill's Crossing, a river crossing near Kakadu, for a unique feeding practice.

Known as floating fish behaviour, crocodiles big and small congregate at the river crossing to take advantage of the swarms of fish heading upstream at certain tides.

"It's a bit like salmon in Canada," said Charlie Manolis​, chief scientist at Wildlife Management International and Crocodylus​ Park.

"At the moment the way the tides are, with mullet coming upstream you're seeing congregations of salties, especially around Cahill's crossing where 30, 40, 50 come together for this event, which really coincides with the warmer weather."

Saltwater crocodiles gather where they know swarms of fish will come through, using their forelimbs with palms outstretched, facing outwards to try and catch fish.

Mr Manolis describes the action as, "like you're trying to corral something with your arms. The fish will hit their arms and they try and eat them."

"But people should not put themselves at risk in those sorts of areas, even if there is only one. They should stand back on the bank and they can observe this stuff till the cows come home," he added.

Crocodile populations in the Top End have bounced back since conservation efforts were put in place to protect the animal. Some experts estimate there are around 100,000 or more in the wild, compared to the 3000 that existed in 1971 when crocodile protection began.

Mr Manolis said the mood around crocodile risk varies greatly.

"Generally when there's an attack there's always, I think, a portion of the public who feel they can't do what they used to do 20 years ago, like swim in certain places … but really, it's a public education thing."

A recent inquest into the crocodile death of Bill Scott at Kakadu last year found that people in boats are still not safe from the reptiles.

Mr Scott, 62, was killed in June last year while on his boat, just two months before Lanh Van Tran was fatally attacked on the banks of the Adelaide River.