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Nile Crocodile

  
The Life of Animals | Nile Crocodile | The Nile crocodile or Common crocodile (Crocodylus niloticus) is an African crocodile which is common in Somalia, Ethiopia, Uganda, Kenya, Egypt, Tanzania, Zambia, Zimbabwe,Gabon, South Africa, Malawi, Sudan, Botswana, and Cameroon. Isolated populations also exist in Madagascar, Senegal.



In antiquity, Nile crocodiles occurred in the Nile delta and the Zarqa River (Jordan), and they are recorded by Herodotus to have inhabited Lake Moeris. It is known from fossil remains that they once inhabited Lake Edward  The Nile crocodile's current range of distribution extends from the Senegal River, Lake Chad, Wadai and the Sudan to the Cunene and the Okavango Delta. In Madagascar, crocodiles occur in the western and southern parts from Sembirano to Port Dauphin. Nile crocodiles have a dark bronze colouration above, with black spots on the back and a dirty purple on the belly. The flanks, which are yellowish green in colour, have dark patches arranged in oblique stripes.
 


 a scaly hide with rows of ossified scutes running down their back and tail; and powerful jaws. Nostrils, eyes, and ears are situated on the tops of their head, so the rest of the body can Smaller specimens can gallop, and even larger crocodiles are capable of surprising bursts of speeds, briefly reaching up to 12 to 14 km/h (7.5 to 8.5 mi/h). The bite force exerted by an adult Nile crocodile has been shown by Dr. Brady Barr to measure 5,000 lbf (22 kN). Hatchlings quickly lose a hardened piece of skin on the top of their mouth called the egg tooth, which they use to break through their egg's shell at birth.Outside water crocodiles can meet concurrence with other dominant Savanna predators, notably felines such as lions and leopards. Occasionally, both will hunt and prey on each other, depending on size, if regular food becomes scarce. The Nile crocodile is the largest crocodilian in Africa and is sometimes regarded as the second largest crocodilian after the saltwater crocodile. The male crocodile usually measure from 11.5 to 16 feet long (3.5 to 5 metres), but very old, mature ones can grow to 18 ft (5.5 m) or more Like all crocodiles they are sexually dimorphic, with the males up to 30% larger than the females, though the difference is even more in some species, like the saltwater crocodile. Mature female Nile crocodiles measure 8 to 13 ft (2.4 to 4.0 m)  Typical Nile crocodile weight is 225 kg (500 lb), though 730 kg (1,600 lb) is possible The largest accurately measured male was shot near Mwanza, Tanzania and measured 6.45 m (21.2 ft) and weighed approximately 1,090 kg (2,400 lb).Dwarf Nile crocodiles also exist in Mali and in the Sahara desert, which reach only 2 to 3 m (6.5 to 10 ft) in length.

Young hatchlings generally feed on smaller prey, preferring insects and small aquatic invertebrates before taking on fish, amphibians and small reptiles. Juveniles and subadults take a wider variety of prey with additions such as birds and small to mid-sized mammals. Throughout its life, both young and mature crocodiles can feed on fish and other small vertebrates on separate occasions, when large food is absent, as a side diet. Adults are apex predators and prey upon various birds, reptiles and mammals in addition to prey consumed also by the young and juvenile specimens. Nile crocodiles also prey on humans frequently, far more often than other crocodilian species (although in parts of the Philippines and New Guinea saltwater crocodile attacks can also be common). This is due to the extensive use of Nile crocodile habitat by people who are unable to afford proper crocodile safety equipment.[citation needed] Although not common, crocodiles can also hunt in packs of five or more individuals while in the water, which can lead to the capture of much larger prey such as hippopotamus and even the Black Rhinoceros

Adult Nile crocodiles use their bodies and tail to herd groups of fish toward a bank, and eat them with quick sideways jerks of their heads. The most dominant crocodile eats first. Their ability to lie concealed with most of their body underwater, combined with their speed over short distances, makes them effective opportunistic hunters of larger prey. They grab such prey in their powerful jaws, drag it into the water, and hold it underneath until it drowns. Groups of Nile crocodiles may travel hundreds of metres from a waterway to feast on a carcass. Once their prey is dead, they rip off and swallow chunks of flesh. When groups of Nile crocodiles are sharing a kill, they use each other for leverage, biting down hard and then twisting their body to tear off large pieces of meat. Herodotus claimed that Nile crocodiles have a symbiotic relationship with certain birds like the Egyptian plover, which enter the crocodile's mouth and pick leeches that have been feeding on the crocodile's blood, but there is no evidence of this interaction actually occurring in any crocodile species, and it is most likely mythical or allegorical fiction.

During the mating season, males attract females by bellowing, slapping their snouts in the water, blowing water out of their noses, and making a variety of other noises. The larger males of a population tend to be more successful. Females lay their eggs about two months after mating .referred nesting locations are sandy shores, dry stream beds, or riverbanks. The number of eggs varies between different populations, but averages around 50. Multiple females may nest close together. The eggs resemble hen eggs, but have a much thinner shell. Both the mother and father may pick up the eggs in their mouths, and roll them between their tongue and the upper palate of their mouth to help crack the shell, and release their offspring. Once they are hatched, the female may lead the hatchlings to water, or even carry them there, in her mouth.Nile crocodiles have Temperature-dependent sex determination (TSD), which means the sex of their hatchlings is determined not by genetics, but by the average temperature during the middle third of their incubation period. Males can only be born if the temperature is within that narrow 5-degree range.The new mother will protect her offspring for up to two years, and if there are multiple nests in the same area, the mothers may form a crèche. The mother will sometimes carry her young on her back to avoid them getting eaten by turtles or water snakes. Crocodile longevity is not well established, but larger species like the Nile crocodile live longer, and may have an average life span of 70–100 years.