Warning as 'humongous' crocodiles in northern Australia keep getting bigger

People have reported seeing crocs in places they never have before before.

Crocodile numbers are on the rise in Australia, prompting authorities to warn locals and visitors to be careful, especially since the average size of the predators is also growing at a rapid rate.

The Department of Biodiversity, Conservation and Attractions (DBCA) recently conducted a survey across East Kimberley rivers — including the King, Ord and Bekerly rivers — to examine and "track the recovery of crocodiles" after historical overharvesting — but the results aren't too surprising says local fisherman Rodney Fischer.

Fischer, who frequents the Ord River near Wyndham in the Kimberley region of Western Australia, suggests the saltwater crocodile population in Australia — found in NT, WA and Far North Queensland — is "just getting back to a healthy amount" after becoming protected in the 70s. Before that, crocodiles were regularly killed — and their eggs taken — en masse for their skin.

Large crocodile alongside boat on Ord River, WA
Crocodiles in northern Australia are getting bigger every year, local Rodney Fischer told Yahoo. Source: Rodney Fischer

"It takes a long time for them to build their population up. The mortality rate of the crocodiles was high," he told Yahoo News Australia, "So it just takes decades for them to build their numbers back up". And that's likely what we're seeing now.

He also said that people are "starting to see more in places where they hadn't seen them before", likely because they're known to move into new territories and take over. "So long as habitats are there, crocs will move back into them and set up their territories and establish their populations there," Fischer said.

Croc population has grown in size

A DBCA spokesperson told Yahoo that "the population of estuarine crocodiles continues to grow by around 8 per cent per year on average".

The Berkeley River plays host to 42 "salties", with a density of 0.9 individuals per km of river surveyed. The Ord River is home to around 2,000 individuals, with an average of seven animals per km of river surveyed. While DBCA staff directly counted a total of 102 different crocodiles in the King.

Close up of large crocodile in Ord River, WA.
The croc population is also growing, with people warned to be careful. Source: Rodney Fischer

"Some of the biggest increases we've seen in the Ord are in the upstream sections, in the freshwater — not just more animals but bigger animals as well," DBCA ecologist Ben Corey told ABC News. Eighty per cent of these were larger than 1.8 metres in length.

Grown into 'humongous, big, beautiful crocodiles'

While female crocs tend to be smaller, usually a maximum length of about three or three-and-a-half metres, the average male is about 4.2 metres, Fischer told Yahoo. But he's often seeing them much, much bigger — and there's reason for that too.

"I've been seeing some five-metre or even five-and-a-half-metre crocodiles on the Ord River," he said. "They've just grown into humongous, nice, big, beautiful crocodiles.

"In the 70s, most of the big crocs were shot leaving a lot of smaller ones behind. And because they can live up to 100 years, we're just starting to see some of those smaller crocodiles that have continued to grow".

Large crocodile laying on ground near Ord River in WA.
The average male crocodile is about 4.2 metres. Source: Rodney Fischer

It's these crocs Fischer claims people are seeing regularly. "But it depends on the food supply too," he said. "Here on the Ord River, there's an endless supply of cattle. So the crocodiles are getting big quicker at a younger age."

Visitors and locals warned to 'be careful'

But the messaging remains the same around croc-infested waters. "People just need to be careful," said Fischer, who films crocodile content for his YouTube channel, Tropical Exposure.

"Take notice of signs when visiting the area and look out for each other," he said. "And don't go into waters where crocodiles live. If people do that, then it'll be alright".

Love Australia's weird and wonderful environment? Get our new newsletter showcasing the week’s best stories.