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From “Can you outrun a crocodile?” to “Do crocodiles really cry?” – the internet has a lot of questions about these prehistoric predators. 

So, we’ve gone to our own Google, aka the herpetologists from Queensland Museum (who are probably more reliable), to fact check some of the most Googled crocodile questions from the internet.  

And some of them are weirder than you’d think. 

Can crocodiles climb trees? 
Why do they sit with their mouths open? 
Are they basically living dinosaurs? 
And perhaps most importantly… should you zig-zag if one chases you? (Short answer: absolutely not.) 

Whether you’re croc-curious, planning a trip to North Queensland, or just trying to win an argument at trivia night, our scientists are here to separate crocodile fact from fiction. 

Ready to dive in? Just maybe not into croc-infested water. 

1. What’s the difference between a crocodile and an alligator? 

Crocodiles and alligators are related but in different families.   The best way to tell them apart is when their mouths are closed, the teeth of a crocodile are still visible (interlocking), whereas in an alligator, only the upper teeth show (overbite).  Crocodiles usually have a narrower, V-shaped snout, while alligators have a broader, U-shaped snout.  Crocodiles are generally more aggressive and can tolerate saltwater thanks to special salt glands.  

2. How big can crocodiles get? 

The largest species, the saltwater crocodile, can grow over 6 metres long and weigh more than 1,000 kilograms. Most adult crocs are smaller than this, but they are still among the largest reptiles on Earth. 

3. What is the largest crocodile ever recorded? 

The largest reliably measured crocodile was a saltwater crocodile named Lolong in the Philippines, measuring 6.17 metres long. Stories of even larger crocodiles exist, but many aren’t scientifically verified. 

4. Are crocodiles dangerous to humans? 

Yes. Crocodiles are apex predators and can be extremely dangerous. Saltwater crocodiles in particular are responsible for attacks on humans. They are ambush hunters with powerful bites and lightning-fast strikes.  Between 2015 and 2024, there were 74 attacks in Australia, eleven of them resulting in human fatality (Croc Attack database, https://crocattack.org/). 

5. How fast can a crocodile run? 

On land, crocodiles can sprint up to around 15–18 km/h over short distances. In water, they are much faster and more agile. 

6. Can you outrun a crocodile? 

Probably, over distance. Crocodiles can only sprint briefly before tiring. The important thing is to move away quickly and never zig-zag; that’s a myth. 

7. How long can crocodiles stay underwater? 

Thanks to a complex cardiovascular system, which can shunt blood away from the lungs when diving, a crocodile can stay underwater for extended periods.  A recent study in Queensland observed crocodiles staying underwater for at least eight hours, longer than any other air-breathing vertebrate.

8. What do crocodiles eat? 

Almost anything they can catch. Young crocodiles eat insects, fish, and frogs, while adults can prey on birds, turtles, pigs, sharks, buffalo, and other animals. 

9. Where do crocodiles live? 

Crocodiles live in tropical regions across Africa, Asia, the Americas, and Australia. They inhabit rivers, wetlands, estuaries, mangroves, and coastal areas. 

10. Are there crocodiles in Australia? 

Yes. Australia is home to two crocodile species: 

• Freshwater crocodile, Crocodylus johnstoni 

• Saltwater crocodile, Crocodylus porosus 

Saltwater crocodiles are found across northern Australia and are the larger, more dangerous species. 

11. What’s the most dangerous crocodile species? 

The saltwater crocodile is widely considered the most dangerous crocodile species due to its size, strength and territorial behaviour. 

12. How long do crocodiles live? 

Many crocodiles live 50–70 years and some may live even longer in captivity.  Cassius, the world’s second largest captive crocodile, was estimated to have been 120 years old at his death in 2024. 

13. Do crocodiles cry tears? 

Yes, but not because they’re emotional. Crocodiles produce tears to lubricate and protect their eyes. 

14. How strong is a crocodile bite? 

A saltwater crocodile has the strongest recorded bite force of any living animal, around 16,000 newtons of force. 

15. Can crocodiles climb trees or fences? 

Surprisingly, yes. Young crocodiles can climb low trees and mangroves and crocodiles have been known to scale barriers and fences. 

16. Why do crocodiles keep their mouths open? 

It helps them cool down. Crocodiles don’t sweat, so they release heat by “gaping” with their mouths open. 

17. How many species of crocodile are there? 

There are 17 recognised crocodile species worldwide, plus ten other related species of alligators, caimans and gharials. 

18. Can crocodiles live in saltwater? 

All crocodiles have glands that excrete salt–on their tongues!  This peculiar adaptation allows them to tolerate living in salt water.  Saltwater Crocodiles seem to have used this ability to spread through the Pacific and Indian Oceans. 

19. Are crocodiles dinosaurs? 

No, but they are ancient relatives. Crocodiles and dinosaurs (including their descendants, the birds) shared a common ancestor about 240 million years ago. 

20. What should you do if you see a crocodile? 

Stay well away from the water’s edge, back away slowly, never feed it and follow all warning signs. If you’re in croc country: 

• Don’t swim in unsafe waterways  

• Keep pets away from the water  

• Avoid standing close to riverbanks  

• Be extra cautious at dawn, dusk, and night  

Australia-Specific Googled Crocodile Questions 

Where are crocodiles found in Queensland? 

Saltwater crocodiles are found in northern Queensland, generally from around Gladstone northwards, including rivers, estuaries, beaches and mangroves. 

Freshwater crocodiles are found inland in rivers and billabongs in northern Queensland. 

Can crocodiles survive in Brisbane? 

Wild crocodiles are not naturally established here, probably because the winters are too cold. Sightings in southeast Queensland are extremely rare and usually involve animals that have travelled long distances or escaped captivity. 

Are there crocodiles at the Great Barrier Reef? 

Yes. Saltwater crocodiles can swim long distances in the ocean and are sometimes spotted around islands and coastal reef areas. 

What’s the biggest crocodile in Australia? 

Some wild Australian saltwater crocodiles are estimated to exceed 6 metres long. Famous large crocs include Cassius (measured 5.48 m in captivity, died 2024) and legendary wild crocodiles from the Northern Territory and Queensland. 

How many crocodile attacks happen in Australia each year? 

Attacks are relatively rare, but they do happen, particularly in northern Australia. Most incidents occur when people swim, fish, or stand close to waterways in crocodile habitat.  See question 4. 

Bonus “Most Googled Myth” 

Do crocodiles really do the “death roll”? 

Yes. Crocodiles spin their bodies rapidly in the water to tear apart prey and gain leverage while feeding. It’s one of their most famous hunting behaviours.