The largest living reptile in terms of linear dimensions is the saltwater crocodile, measuring 7.3-9.1 meters (24-30 ft) and up to 1,700 kilograms (3,700 pounds). Much larger prehistoric reptiles existed, including the land-dwelling Sauroposeidon, Titanoboa cerrejonensis, which could reach lengths of 11.1-15 meters (36–50 ft), and even larger marine reptiles such as Mosasaurus hoffmanni, estimated to have measured about 12 metres long.
The saltwater crocodile is a large, aggressive and opportunistic reptile that can be found in very large numbers throughout Southeast Asia. A prime hunting ground for them is the Sundarbans in Bangladesh. A smaller cousin of the crocodile, it is also known as the estuarine crocodile or “saltie”. At birth they are about 1 metre (3.3 ft) long. They can grow at a rate of 4-5 inches per year. Before becoming sexually mature, males are usually 2 to 3 metres (6–10 ft) long and weigh up to 700 pounds . A mature male will have distinctively thick muscular neck, with an alligator-like gait when walking on land. The overall shape of the males is more streamlined than that of females; this is so that the male can move easily in water. Males also tend to be slightly larger than females with a recorded length up to 5 m (16 ft), and can weigh up to 1000 pounds .
The saltwater crocodile’s diet consists of a wide variety of animals. Their prey includes fish, birds , turtles, crabs, monkeys, monitor lizards , water buffalo calves, wild boar piglets and domestic livestock such as cattle and dogs. The animals that the saltwater crocodile attacks are typically around its own size or larger. There have been many reported cases where humans have been attacked by them while swimming in waters where they live.