How long do they live? Saltwater crocodiles can live over 70 years and it is theorized that they can easily live over 100 years old. As with the American alligator, it’s nearly impossible to estimate the age of a crocodile without knowing the date it hatched. Size to age estimates are inaccurate because these species do not grow continuously throughout their life; they experience times of extremely slow growth.
Where are they found? Saltwater crocodiles can been found along the northern coastal regions of Australia and the coasts of neighboring countries . They can travel in saltwater, but prefer the brackish water of mangrove swamps and freshwater inlets.
What do they eat? They are not picky. If a crocodile is hungry then it will pretty much eat anything, such as dingoes, cattle, wallabies, your dog, and even other crocodiles.
What do they look like? A picture is worth a thousand words, so see figures 1, 2, 3 and 4. Male crocodiles can grow to 20 feet long or larger and weigh over 2,000 pounds .
How do they reproduce? Sexual maturity is reached between 10 to 16 years old . Female Saltwater crocodiles will bury their eggs on land and return to care for the young when they begin to hatch. They not only uncover the eggs and assist in hatching, but they will escort the babies to the water via their mouth. The babies will stay with their mom for a few months and then it’s time to move on to marking out their own territory. Even though a female can lay up to 90 eggs, very few will hatch and even fewer will survive due to predation by other (extremely ballsy) animals. I could not track down any reproductive senescence studies for this species.
How do scientists know how old they are? Researchers must know when the crocodile hatched to truly know the age of the reptile. Some estimates have been made based on size, but that’s not accurate at all. Given a better technique for age identification and based on what we are finding out about sharks and whales, I would not be surprised if we soon discover that Saltwater crocodiles are another species with negligible senescence.
So what are we lacking? Decent techniques for age verification and information regarding reproductive senescence.
What do we have? The nuclear genome of Crocodylus porosus can be accessed on the NCBI website.
Conservation status: Although this species is listed as Least Concerned on the IUCN, keep in mind it is an outdated list from 1996. Australia is experiencing an enormous amount of growth and thus habitat loss for many species. Humans are a major threat to Saltwater crocodiles because people would rather see them made into a purse or wallet than appreciate the beauty of them in the wild. Just like the American alligator people are scared of crocodiles and therefore find it easier to kill them before they can kill us. Ironically, we kill far more crocodiles per year than they kill humans. We also walk right into their homes and tear it down, a feat that other animals have not done to us, yet.
- Crocodile Specialist Group. 1996. Crocodylus porosus. The IUCN Red List of Threatened Species 1996: e.T5668A11503588. Accessed 11/7/2016
- Animal Diversity Web. Saltwater crocodile. Accessed 11/7/2016 http://animaldiversity.org/accounts/Crocodylus_porosus/