Living With Wildlife

Crocodile

Family: Crocodylidae

Scientific names: Crododylus johnstoni (Freshwater crocodile) Crocodylus porosus (Estuarine crocodile)

Crocodiles in the Environment

Freshwater and estuarine (saltwater) crocodiles are found in the Northern Territory. Freshwater crocodiles, which are also referred to as ‘freshies’, and can be found throughout inland river and lagoon systems across the Top End, including the Katherine, Victoria River and Mataranka regions. Contrary to what their name suggests, Estuarine crocodiles (also known as Saltwater crocodiles or ‘salties’) are found across a wide range of habitats, including in freshwater and saltwater environments. Estuarine crocodiles inhabit all Top End coastal waters, rivers and wetland systems and may be found in watercourses more then 300km inland.

Both species of crocodile rely on external heating (known as thermoregulation) and can often be seen basking out of the water in cooler weather.

Feeding

Crocodiles are carnivorous and feed on a wide range of items, including fish, frogs, birds, mammals, crustaceans and reptiles (including other crocodiles). Freshwater crocodiles are restricted to smaller prey items due to their slender snout, such as fish and freshwater crustaceans. Estuarine crocodiles, on the other hand, utilise their bulky powerful snout and jaws to feed on just about any animal living in or entering the water, including wallabies, pigs, turtles, horses and occasionally humans.

Crocodiles are important predators and help maintain healthy ecosystems through population control of species such as wallabies, fish and waterbirds. Crocodiles are also known to prey on a range of introduced pest animals, including feral pigs and dogs.

Threats

In the early 1970s, Estuarine crocodiles were on the brink of extinction, with broad scale unmanaged hunting occurring throughout the Top End. In 1971, crocodiles were awarded full protection under the Territory Parks and Wildlife Conservation Act which allowed for populations to recover. Today, the Northern Territory has the largest Estuarine crocodile population in Australia. Researchers continue to monitor estuarine crocodile populations and permitted annual harvesting.

Recent reports suggest that Freshwater crocodile populations may suffer with the spread of the Cane toad which has enough poison to kill a small crocodile. Moreover, anecdotal evidence suggests that Freshwater crocodiles will perish as a result of consuming a Cane toad; however the impacts on their populations are largely unknown. In urban areas, crocodiles may also occasionally fall victim to boat strikes and accidental drowning in fishing nets due to their close proximity to humans.

Interactions With People

In areas occupied by humans, crocodiles take advantage of opportunistic food supplies, regular visitation by potential prey such as livestock and pets, and easy land access via boat ramps and crossings. The Parks and Wildlife Service actively manages problem crocodiles, which are broadly defined as individuals that occur within settled areas or areas of recreational use, and areas where public safety is a prime consideration. Interactions between humans and crocodiles should be minimised were possible, particularly in areas known to support saltwater crocodiles.

What You Can Do

When visiting crocodile habitat remember to always adhere to the following precautions:

Always read and obey warning signs.
Never swim in crocodile habitat. Remember crocodiles may be in the area even if there are no warning signs.
Always clean fish and camping equipment at least 50m from the edge of the water.
Never dump food waste or rubbish near the water, as this may attract crocodiles to the area.
Always keep away from ‘slides’, the characteristic marks left by crocodiles on the embankment when entering and exiting the water.
Never interfere with, feed or harass crocodiles; even small crocodiles can inflict serious damage when provoked.
Always take particular care at night and during breeding season when crocodiles are most active.
Never dangle any part of your body over the side of a boat, jetty or any overhanging logs or trees.
Ensure pet dogs are kept out of and away from the water, as they may attract crocodiles to the area.
Never camp at the waters edge or use low lying watercraft, such as canoes, in saltwater crocodile habitat.

If you have a problem crocodile in your area, you should contact Parks and Wildlife staff on the details below.

Darwin 0419 822 859 or 8999 4691
Katherine 0407 958 405 or (08) 8973 8888

Crocodiles are a protected species in the Northern Territory. For this reason, it is important that members of the public do not interfere with these animals without an appropriate permit.