Staying Safe Around Saltwater Crocodiles

The Estuarine or 'Saltwater' crocodile is the largest living reptile on the planet today. Known for their ferocious aggression, they have the strongest bite force of any animal ever recorded, (with 3,700 pounds per square inch (psi), or 16,460 newtons of pressure).

Despite adults weighing in at over 1,000 kilograms, they're able to exit the water with explosive speed when ambushing prey - around 12 metres per second, per second - or 43kph.

Such speeds last a very short time and are not maintained - because they don't bloody have to be.

Croc cruising on the river

Master of its domain


I call this Croc "chainsaw" - he's awesome

Another - not to be trifled with

Crocs are primarily ambush predators, relying on their superb camouflage and highly evolved senses to capture food. These senses include ISO's or DPR's (integumentary sense organs or dome pressure receptors).

These organs enable the crocodile to feel pressure changes in the water via vibrations caused when animals, such as fish - or people, swim.

Often Crocs seem lethargic - but don't be fooled

Deceptively 'peaceful'

The term 'Salty' is a bit of a problem, as the Estuarine crocodile can be found in any water-way within its range, irrespective of salinity. For a croc, consistent temperature gradients and food availability are far more pressing concerns.

That said, they are often found in salty to brackish water and have developed special glands to deal with the build up of sodium chloride in their bodies.

In the estuarine crocodile, Crocodylus porosus, clear fluid exudes from numerous pores scattered over the upper surface of the tongue.

The secretion is stimulated by injection of methacholine chloride, ishyperosmotic to the body fluids, and contains high concentrations of both sodium and chloride


Adult estuarine crocodiles are northern Australia's undisputed apex predators, but life in the beginning is tenuous at best:

Breeding territories are usually established along tidal rivers, creeks and freshwater areas. Females reach sexual maturity at lengths of 2.2 to 2.5 m (10 to 12 years old).

Males mature later (3.2 m, at/or around 16 years old). Females on average lay 40 to 60 eggs (this can range from 25 to 90) in mound nests made from vegetation, usually grasses, vines and mud. For saltwater crocodiles, flooding is the main cause of embryo mortality, not predation


Females stay near the nest, and will defend it vigorously - even to the death. Juveniles hatch after 80 to 90 days, (this varies with temperature - 80 days at a sustained 32 Celsius, longer if cooler).

Mum will dig hatchlings out of the nest when they start their characteristic chirping sounds, assisting some of them to the water by picking them up and carrying them within the mouth.

It's estimated that less than 1% of hatchlings will survive to reach maturity, due to flooding, predation, and social pressures, (territorial males will kill and eat juveniles)

Would you believe Crocs can climb?

Juv Crocodylus porosus 7–8 weeks old atop a broken tree stump


A "Bull" Croc ...

A battle-scarred adult 'Bull'

The little guy pictured had climbed some considerable distance up that stump and will leap to the safety of the water at the first hint of danger.

A young croc - in its prime

Just blissing out - but don't be fooled

Crocodiles are at home in the water - it is their preferred environment and normally only venture onto land to lay their eggs or thermoregulate. They do not, as a rule, actively hunt on land ... of course, you know what they say about rules ...

A NINETEEN-year-old man is in hospital in Katherine after he was attacked by a crocodile in his tent this morning.

Peter Roswell was on a camping trip with his family at Palm Creek near Bradshaw when he was attacked at 4.30am.

Department of Health spokeswoman Gail Liston told the NT News the crocodile bit his right foot. The man managed to free himself from the crocodile’s jaws. The crocodile then slid back into the water.


The snippet above is really just the tip of the iceberg. A simple online search will turn up numerous accounts of people being attacked on land, usually while sleeping. This points to some other salient facts regarding crocodile behaviour:

1. They are nocturnal (although often seen moving about during the day)
2. They are opportunistic hunters

Knowing this - it stands to reason that the recommended safe distance to camp from waterways in croc country is at least 50 metres - no, seriously.

Here are some guidelines to take note of if you're unfamiliar with crocodiles (or, in fact - if you've been around them your entire life)

  • Obey crocodile warning signs, they are there for your safety and protection.
  • Never swim in water where crocodiles may live even if there is no warning sign present.
  • Swimming or standing in water above knee-height near a crocodile warning sign or where estuarine crocodiles are frequently seen, is illegal in protected areas (you can still enter the water if you have a reasonable excuse, e.g. launching a boat).
  • When fishing, always stand a few metres back from the water's edge and never stand on logs or branches overhanging the water.
  • Never clean fish or discard fish scraps near the water's edge, around campsites or at boat ramps.
  • Stay well back from any crocodile slide marks. Crocodiles may be close by and may approach people and boats.
  • Boats and vehicles must never be brought within 10 m of an estuarine crocodile in the wild - it is illegal unless part of a commercial crocodile viewing tour, or there is a reasonable excuse, e.g. where a creek is less than 10 m wide.
  • Never dangle your arms or legs over the side of a boat. If you fall out of a boat, get out of the water as quickly as possible.
  • Never provoke, harass or interfere with crocodiles, even small ones.
  • Never feed crocodiles - it is illegal and dangerous.
  • Camp at least 2 m above the high watermark and at least 50 m from the water's edge. Avoid places where native animals and domestic stock drink.
  • Never leave food scraps, fish frames or bait at your campsite. Always check that previous campers have not left these behind.
  • Never prepare food, wash dishes or pursue any other activities near the water's edge or adjacent sloping banks.
  • Be more aware of crocodiles at night and during the breeding season, September to April.

Always keep in mind that the estuarine crocodile is one of the very few animals (along with the Polar bear and Tiger/Bull sharks), who view human beings as prey.

Between 1838 and 1902 it was illegal to swim at the beach during the day!


A "yawning" display - just to let us know who's who and what's what!

'Yawning'

A little surprisingly crocodiles are quite communicative - both by using body language and audible sounds. The croc above yawned spectacularly (the jaws in this pic are about half-way open) and such displays are probably a warning to interlopers that the animal is not in the mood to be trifled with.

But please remember that on the whole, stealth and camouflage are their forte, just because you cannot see a crocodile does not mean that it hasn't seen you.

The animal below might look a little comical - but crocodiles have been recorded 'creating' perches as an ambush trap for unsuspecting birds.

Do Crocs use tools?

Need somewhere to land?

At the end of the day, we might accept that life is a risk. However, in the case of crocodiles, we really only need to be informed, and willing to modify our behaviour when venturing into their habitats to mitigate the risks that crocs pose.

It also pays to keep in mind that in Australia:

According to statistics compiled by the National Coroners Information System, horses are the animals most likely to cause a human death.

Cows are the next most dangerous, followed by dogs.

Sharks are in fourth position, while crocodiles and spiders account for only slightly more deaths than emus, cats and fish.


Despite these facts, ya don't see anyone calling for a cull of horses, do you?

Something to think about, eh?

I hope you got something out of this post and, as always - take care

The saltwater crocodile (Crocodylus porosus), also known as the estuarine crocodile, Indo-Pacific crocodile, marine crocodile, sea-going crocodile or informally as salty, is the largest of all living reptiles, as well as the largest terrestrial and riparian predator in the world.

Males of this species can reach sizes up to at least 6.30 m (20.7 ft) and possibly up to 7.0 m (23.0 ft) in length.

However, an adult male saltwater crocodile rarely exceeds a size of 6 m (19.7 ft) weighing 1,000 to 1,200 kg (2,200–2,600 lb), females are much smaller and often do not surpass 3 m (9.8 ft). As its name implies, this species of crocodile can live in salt water, but usually resides in mangrove swamps, estuaries, deltas, lagoons, and lower stretches of rivers.

They have the broadest distribution of any modern crocodile, ranging from the eastern coast of India, throughout most of Southeast Asia, and northern Australia.

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