Tropical to warm temperate latitudes in the eastern Indian and western Pacific oceans
Mangrove forests and other coastal habitats
Order Crocodilia (alligators, crocodiles, and relatives), Family Crocodylidae (crocodiles)
Reaching lengths of more than 23 feet (6.5 m) and weights over 2,200 pounds (~1,000 kilos), the saltwater crocodile is the largest reptile on the planet and is a formidable predator throughout its range. Saltwater crocodiles of this size are capable of eating just about any animal that strays too close and are particularly adept at drowning terrestrial creatures like birds and mammals. Named for its ability to survive in full salinity seawater, saltwater crocodiles typically live in brackish (low salinity) water near the coast.
Though crocodiles and their relatives have a negative reputation among people, most species are relatively harmless and would rather avoid people rather than confront them. The saltwater crocodile, however, is known to show aggression towards people – partly a result of its strong territoriality – and is responsible for at least several dozen attacks on people each year.
The extremely powerful jaws of the saltwater crocodile are responsible for creating the strongest bite in the animal world. The strong teeth can be up to five inches (13 cm) long. These two characteristics and the animal’s ability to hold its breath for long periods of time make it the perfect predator for hunting large land mammals. Saltwater crocodiles lurk along the water’s edge and attack in a violent lunge at any potential prey that approaches the water. The crocodiles are an old lineage and have been thriving in this environment since before the dinosaurs went extinct. In many superficial ways, the saltwater crocodile seems to resemble a dinosaur.
Though they spend much of their time in the water, saltwater crocodiles must come ashore to warm up in the sun and to nest. Like all reptiles, saltwater crocodiles reproduce via internal fertilization, and females carefully look over their nests after laying a clutch of approximately 50 eggs. In addition to protecting their eggs from potential predators, females carry new hatchlings to nearby bodies of water so that they will not be harmed during that dangerous first journey and continue to protect the young for at least several months. Interestingly, the temperature of the nest determines the sex of the hatchlings. Cooler nests produce mostly females, while warmer nests produce mostly males.
Though they have few natural predators, saltwater crocodiles have been hunted for many decades by people. Their eggs and meat are eaten, and their skin is particularly valuable for use as a material for bags, shoes, and other goods. These activities have threatened the saltwater crocodile’s numbers in the past, and this species has historically been considered highly vulnerable to extinction. Recent conservation efforts have allowed populations to rebound in some places, but the historic range has certainly contracted, as a result of local extinction. Currently, the saltwater crocodile has complete legal protection in Australia and other places. However, it is important to further monitor saltwater crocodile population trends to ensure that the recent positive trend continues to support recovery of this top coastal and marine predator.
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