Saltwater Crocodile - Diet and Behaviour

Diet and Behaviour

The saltwater crocodile is an opportunistic apex predator capable of taking nearly any animal that enters its territory, either in the water or on dry land. Like most crocodilians, they are unpicky eaters who readily vary their prey selection based on availability but are not voracious eaters, as they are able to survive on relatively little food for a prolonged period. The Saltwater crocodile may take animals of almost any variety as it becomes available to them and, due to the enormous power and size of the species, it may take the broadest of prey species of any modern crocodilian. Juveniles are restricted to smaller animals such as insects, amphibians, crustaceans, small reptiles, and fish. The larger the animal grows, the greater the variety of animals it includes in its diet, although relatively small aquatic prey (especially fish) make up an important part of the diet even in adults. Large adult saltwater crocodiles can potentially eat any animal within their range, including monkeys, kangaroos, wild boar, dingos, snakes, turtles, goannas, birds, domestic livestock, pets, humans, water buffalo, gaurs, bats, and even sharks. They are dominant over other crocodilians, regularly outcompeting them and occasionally killing and eating other species, as has been recorded largely with freshwater crocodiles in Australia. In 2011 a large saltwater crocodile killed a Bengal tiger when the tiger was crossing a river – the only known attack of this kind. Domestic cattle, horses, water buffalo, and gaur, all of which may weigh over a ton, are considered the largest prey taken by male crocodiles. Perhaps the Asian elephant and the Asian rhinoceros species are the only non-marine animal in this species' range that this crocodile has not been known to predate. They are known to attack humans who enter their territory.

Generally very lethargic – a trait which helps it survive months at a time without food – it typically loiters in the water or basks in the sun through much of the day, preferring to hunt at night. Saltwater crocodiles can swim at 15 to 18 miles per hour (6.7 to 8.0 m/s) in short bursts, around three times as fast as the fastest human swimmers, but when cruising they usually go at 2 to 3 mph (0.9 to 1.3 m/s). Saltwater crocodiles are capable of explosive bursts of speed when launching an attack from the water, but stories of crocodiles being faster than a race horse for short distances across land are little more than urban legend. At the water's edge, however, where they can combine propulsion from both feet and tail, their speed can be considerable, though eyewitness accounts are rare.

It usually waits for its prey to get close to the water's edge before striking, using its great strength to drag the animal back into the water. Many prey animals are killed by the impact of the great jaw pressure of the crocodile, although some animals are killed by drowning after the crocodile has pulled them into the water. It is an extremely powerful animal; in one case, a one-tonne Suffolk stallion known to haul over two tonnes was pulled into water to its demise by a large male crocodile. A large crocodile can crush a full-grown bovid's skull between its jaws. Its typical hunting technique is known as the "death roll": it grabs onto the animal and rolls powerfully. This throws any struggling large animal off balance, making it easier to drag it into the water. Like all crocodilians, the sharp but peg-like teeth are well suited to seize and kill various prey, but they are not well-suited to tearing flesh off of large prey items as is the dentition of many mammalian carnivores or the hooked bills of raptorial birds. Whereas prey such as fish and crabs are swallowed whole, larger prey of the Saltwater crocodile are thrashed around after they're killed, often either in a "death roll"-like action or by being flung back and forth in the air, until a limb or chunk of flesh separates and can be swallowed.

While adults have no natural predators, baby saltwater crocodiles may fall prey to monitor lizards, predatory fish, various aquatic and raptorial birds, larger crocodiles and other predators. Juveniles may also fall prey to tigers and leopards in certain parts of their range, although encounters between these predators are rare and cats are likely to usually avoid areas with saltwater crocodiles. In one case, in the Sundarbans region, a tiger was reportedly hit in the face with the tail of a "small crocodile" of this species, drawing blood, but then the big cat turned on the reptile pawing it about the face, flipping it over and tearing open its belly.