Crocodiles have three eyelids. In addition to the top and bottom eyelids, there’s a mostly transparent lid that cleans the eye and protects it when underwater.

Crocodiles do not have any vocal chords, so noise is made by pushing air through the throat and nostrils.

Crocodiles can judge the distance to their target very accurately – they have binocular vision.

Once ready to ‘lunge’ a crocodile immediately starts to use its tail to literally push itself upwards out of the water.

Crocodiles rely on the process of thermoregulation to regulate their body temperature – cooling in the water and warming in the sun. Keeping its mouth open while warming stops overheating of the brain.

Northern Australia is home to as many as 150,000 saltwater crocodiles.

The largest crocodile found in Australia's Northern Territory measured over 20 feet long and was found in 1974.

Crocodiles can start life weighing less than 2 ounces, but at maturity can grow to over 2,000 pounds.

A female crocodile lays an average of 40 to 60 eggs per season.

It is believed that less than 1% of these eggs reach adulthood due to flooding of nests, predation and overheating.

At 31.6 degrees, most of the hatchlings will be males. A couple of degrees above and below this, and most of the hatchlings will be females.

Despite their name, saltwater crocodiles are found in both fresh and saltwater and have been seen in water as far as 300km (186 miles) inland.

In the 1970s, saltwater crocodiles almost became extinct in the Northern Territory. The government introduced a law which tightly controlled hunting practices, allowing the population to regenerate.