Alligators are only generally found in freshwater environments, while crocodiles can be found in both freshwater and saltwater—although they can't live in the ocean, preferring to stick to river estuaries.
Crocodiles live near water. Any time you are near billabongs, creeks, rivers, the beach or other swimming holes in the northern part of Australia you should be aware that there is a chance of a crocodile living nearby.
In Queensland the Salt-water Crocodile inhabits reef, coastal and inland waterways from Gladstone on the east coast, throughout the Cape York Peninsula and west to the Queensland-Northern Territory border.
Crocodiles are an ancient and fascinating species, but they can also be dangerous if you don't give them the proper respect. They can be found in estuaries and beaches around Tropical North Queensland as well as in rivers, lagoons and swamps hundreds of kilometres from the sea.
As you may have guessed by their name, the saltwater crocodile can live in saltwater, brackish or even freshwater habitats. Saltwater crocodiles are well-suited for saltwater and brackish environments thanks to their lingual salt glands.
Yes, there are crocodiles in Cairns and its surrounds. With Australia territory that stretches across the top end of Western Australia, Northern Territory and Queensland, you'll most likely see saltwater crocodiles during your time in north Queensland.
So when answering this particular question of how far do they swim out into the ocean, consider how far out they are being carried by the currents. It is estimated that they can be carried out approximately (on average) about 48km (or 30 miles).
More crocodiles in the NT
There is estimated to be around 100,000 saltwater crocodiles in the wild in the NT. There are more saltwater crocodiles in the NT than Queensland and Western Australia (WA).
Interesting facts about crocodiles
The Mary River in the Northern Territory has 15 crocodiles per km, making it the most densely populated river! The temperature of the egg determines the sex of the animal.
Only swim at patrolled beaches (a beach where there are lifeguards on duty) and always swim between the red and yellow flags where lifeguards can see you. Many Australian beaches have 'rips'. These are strong underwater currents that can be hard to spot but which can draw you away from the shore quickly.
Bondi Beach is considered the safest beach in Australia. It's one of the most popular beaches that has lifesavers patrolling the beach all day. Bondi Beach is considered the safest beach because of the number of patrolled lifeguards for those swimming, you should swim only on patrolled beaches.
Listen for Hissing
This crucial warning sign is often a loud hissing noise that tells you that you're in its territory. If you hear this sound, you should slowly retreat to safer waters to avoid a confrontation.
Saltwater crocs, or "salties," as Australians affectionately refer to them, have an enormous range, populating the brackish and freshwater regions of eastern India, Southeast Asia, and northern Australia. They are excellent swimmers and have often been spotted far out at sea.
The largest living reptile documented by science is the saltwater crocodile. They ambush their prey before drowning and swallowing them whole. The saltwater crocodile is one of the only crocodiles able to regularly kill and eat sharks.
Croc Country (considered to be typical crocodile habitat) begins at the Boyne River south of Gladstone, and extends northward, up the east coast and across far north and north west Queensland to the Northern Territory border. Crocodiles can sometimes also be found outside of croc country.
Australia has a large population of crocodiles but as the research noted, there are only an average of 1.9 attacks a year.
Too cold to stay
Regardless of how lone crocodiles end up in northern New South Wales and southern Queensland, experts say crocodile populations never inhabited the regions. Dr Salisbury said any crocodiles that ended up in unusually southern locations, were almost always alone and never stayed for long.
Back in July 1957, Australia's largest known crocodile, 8.64 metres long, was killed with a single shot on the banks of the Norman River by a Polish immigrant Krystina Pawlowski. The shot made her a worldwide celebrity and earned her the nickname One Shot along with a place in the Guiness Book of Records.
Saltwater crocodiles are typically found in the murky waterways, rivers, lakes, and swamps in the Northern region of Australia. However, on occasion, they can be found in the ocean region, with the beaches and islands in the Great Barrier Reef known to have an occasional croc sighting.
"World's Most Aggressive Crocodiles"
In December 2013, a study conducted by researchers at Charles Darwin University in the Northern Territory found that the saltie was much more aggressive than six other species of crocodiles from around the world.
Central Africa has the largest population of Nile crocodiles. The southeast Asian island of Borneo also has a large population of estuarine crocodiles.
The beaches in the city aren't suitable for swimming due to crocodiles and it being too buddy. However, there is a lagoon to swim in if you're staying in Cairns City.
Places to Swim in Cairns
The best beaches for swimming near Cairns are Trinity Beach, Palm Cove, Ellis Beach and Holloways Beach. All four of these sandy tropical oases are patrolled year-round and are protected by stinger nets in the summer season (November to March/April).
You are responsible for your own safety, so please follow these guidelines and be crocwise in croc country. Obey crocodile signs—they are there for your own protection. Never swim in water where crocodiles may live, even if there is no warning sign present.