Crocodile Numbers in Queensland Reveal their Recovery from Near Extinction

A new Queensland Government survey shows that crocodile populations throughout Queensland continue to recover after the reptiles were almost hunted to extinction before being protected in the 1970s.

Department of Environment and Science Wildlife Program Coordinator, Dr Matt Brien has led a three-year Queensland Estuarine Crocodile Monitoring Program. He reports that their research results show the current estuarine crocodile population is estimated at between 20,000 – 30,000 non-hatchling animals.

This was the most comprehensive crocodile population monitoring program to be carried out in Queensland since the 1994-2003 survey and involved extensive spotlight and helicopter surveys of river systems. A highly trained team surveyed rivers in Cape York and the Gulf and as far south as Maryborough on the east coast and detected no crocodiles south of the Fitzroy River, Rockhampton.

“The population recovery has been relatively slow and highly variable across the ranges of species since the unregulated hunting of estuarine crocodiles for their skins was banned.”

Department of Environment and Science Wildlife Program Coordinator, Dr Matt Brien

“The average rate of population growth for the species across its range is 2.2 per cent per year and only 20 per cent of its population is found south of Cooktown.

“The survey showed the spatial distribution of crocodiles in Queensland has not changed, and there is no evidence of any southward expansion of its range.

“Due to the limited amount of suitable nesting habitat, the Queensland crocodile population is not expected to reach the size or density of the Northern Territory crocodile population.”

Interestingly, the results show that while crocodile numbers have increased along Queensland’s east coast, the survey showed the average size of the animals has decreased.

“This is a likely consequence of the Queensland Government’s crocodile management program, where crocodiles assessed as posing a threat to public safety are removed from the wild – with more than 450 crocodiles having been removed from 2004 to 2019.”

Department of Environment and Science Wildlife Program Coordinator, Dr Matt Brien

Environment Minister Meaghan Scanlon said as part of its budget, the Palaszczuk Government would invest an initial $12 million over the next four years for the ongoing management of crocodile populations and make its CrocWise program permanent – funding able to be delivered because of the continued rollout of the state’s economic recovery plan from COVID-19.

“With croc populations slowly increasing, it’s important that we continue our CrocWise program and make sure human safety remains the number one priority,” Minister Scanlon said.

“This funding is part of our record $1.4 billion investment in the environment and to rollout Queensland’s COVID-19 economic recovery plan.

“The Chief Scientist will now review the data, and what it means for our communities. For many northern and far north Queenslanders, they’ve lived during a time when crocodile populations were relatively low, after being hunted to near extinction.

Minister Scanlon said the review would involve looking at how wildlife officers and scientists can respond to population trends, improve the management program and bolster public safety through ongoing education programs.

“It might mean we need to target our CrocWise program to more places like beaches and watering holes, where people might’ve never seen a crocodile before.

Minister Scanlon said the rebounding numbers is good news from a conservationist perspective, but it shows there’s never been a more important time for people to exercise vigilance in croc country and to make the CrocWise program permanent.

“Since 2012, we’ve ramped up annual funding for crocodile management to the point where it’s now almost eight times the amount invested under the previous government.

“While crocodile populations aren’t like that in the NT, we have wildlife officers on the ground who remove problem crocodiles – and this survey will allow rangers to now look at how they can build on that expertise.

“But it remains crucial for people to continue to be vigilant when in croc country, whether that’s following the signage, reporting crocodiles, staying away from croc traps and fishing safely.”

Queenslans environment Minister, Meaghan Scanlon

Dr Matt Brien said members of the International Union for the Conservation of Nature (IUCN) Crocodile Specialist Group had reviewed the design of the monitoring program and subsequent technical report, and that a committee led by Queensland’s Chief Scientist would now review Queensland crocodile management program in the context of the report’s findings.

All crocodile sightings can be reported by using the free QWildlife app or by calling 1300 130 372. DES investigates all reports it receives.

Survey Fast Facts

  • 56 boat surveys were conducted in 42 rivers covering 2,200 km
  • 14 helicopter surveys were conducted in 27 rivers covering 2,500 km
  • The number and density of crocodiles are highest in northern Cape York Peninsula (3/km)
  • The number and density of crocodiles declines southward with 1.2/km in the Gulf of Carpentaria and Cairns region, down to 0.2/km in Rockhampton’s Fitzroy River
  • About 20 per cent of Queensland’s crocodile population is found on the populated east coast from Cooktown to Rockhampton
  • Previous surveys occurred in 1979, 1984-89, and 1994-2003