Nile crocodile (Crocodylus niloticus) is a common African crocodiles in Somalia, Ethiopia, Uganda, Kenya, Egypt, Tanzania, Burundi, Zambia, Zimbabwe, Gabon, South Africa, Malawi, Sudan, South Sudan, Botswana and Cameroon. There is also an isolated population in Madagascar and Senegal.
In the old days, Nile crocodiles occurred in the Nile Delta and the Zarqa River (Jordan), and they are recorded by Herodotus was inhabited Lake Moeris. They unexpectedly stalling in the Seychelles in the early 19th century. They are known from fossil remains have been inhabited Lake Edward. Nile Crocodile current distribution range extends from Senegal River, Lake Chad, Sudan and Wadai to Cunene and Okavango Delta. In Madagascar, crocodiles occur in the west and south of Sembirano to Port Dauphin. They are sometimes seen in Zanzibar and Comoros. Until recently, many permanent water in the Sahara still housed relict populations.
In East Africa, they are mostly found in rivers, lakes, marshes, and dams. They have been known to enter the sea in some areas, with a specimen that has seen 11 kilometers (6.8 miles) from St. Lucia Bay in 1917. In Madagascar, they have adapted to living in caves.
This species previously considered to extend to West Africa, but this population is now recognized as a distinct species, crocodiles desert.
Nile crocodiles have a dark bronze colouration above, with black spots on the back and a dirty purple on the belly. Hip, yellowish green in color, have dark spots set in oblique lines. There is some variation relative to environment, specimens from the fast-flowing water tends to be lighter in color than live in lakes or swamps. They have green eyes.
Like all crocodiles, the Nile crocodile is a quadruped animal with four short, legs outstretched, a long tail, strong, scaly hide with rows of stiff Scutes flowing back and tail, and a strong jaw. This pengerjap membrane to protect the eyes and tear glands to clean his eyes with tears. Nostrils, eyes, and ears are situated on top of the head, so that the entire body can remain concealed underwater. Color also helps to disguise themselves, youth gray, multicolored, or brown, with darker cross-bands on the tail and body. Until they become due, become darker and dull cross-band, especially on the body. Belly yellowish green, and make high-quality leather.
They normally crawl along on their bellies, but they can also "high walk" with their trunks raised above the ground. Smaller specimens can be driven, and even a large alligator able to surprise spray speeds, briefly reaching up to 12 to 14 km / h (7.5 to 8.7 mph). They can swim much faster by moving their body and tail with a meandering way, and they can maintain a longer form of movement around 30 to 35 km / h (19 to 22 mph).
They have the heart of a four-room, although altered to their ectothermic nature as an elongated cardiac septum, similar physiological heart of a bird, which is especially effective oxygenating their blood. They usually dive only a few minutes, but will remain under water for 30 minutes if threatened, and if they remain inactive they can hold their breath for up to two hours. They have an ectothermic metabolism, so that it can survive for long periods of time between meals-even as they eat, they can eat up to half their body weight at a time.They have a rich vocal range, and good hearing. Their skin has a number of poorly understood integumentary sense organs (ISOs) that can respond to changes in water pressure.
Bite strength provided by adult Nile crocodile has been shown by Dr. Brady Barr to measure 5.000 lbf (22 kN). However, the muscles responsible for opening the mouth are exceptionally weak, allowing a man to easily hold them shut with a small amount of power. Their mouths are filled with a total of 64 to 68-cone-shaped teeth. On each side of the mouth, there are five teeth in the front of the upper jaw (premaxilla), 13 or 14 around the upper jaw (maxilla), and 14 or 15 on both sides of the lower jaw (mandible). Tukik quickly lose a piece of hardened skin on the top of their mouth called the egg tooth, which they use to break through their shell at birth.
Outside water crocodiles can meet the competition from dominant savanna predators, especially cats such as lions and leopards. Sometimes, the two big cats and crocodiles will hunt and prey on each other, depending on the size, if regular food became scarce.
Nile crocodile is the largest crocodile in Africa and is sometimes regarded as the second largest after the crocodile saltwater crocodiles. Male crocodile usually measure from 3.5 to 5 meters (11 to 16 ft) long, but very old, the adult can grow up to 5.5 m (18 ft) or more. Like all crocodiles they are sexually dimorphic, with males up to 30% larger than females, although the difference is even more in some species, such as salt water crocodiles. Adult female Nile crocodile size from 2.4 to 4 m (7 ft 10 to 13 ft 1 in). Nile crocodiles Special weight is 225-500 kg (500 to 1.100 lb), although a large male can range up to 750 kg (1,700 lb) in mass. Male largest accurately measured, was shot near Mwanza, Tanzania, measured 6.47 m (21.2 ft) and weigh about 1,090 kg (2,400 lb).
Seven meters and larger specimens have been reported, but as a general measure of gross too high, this report is suspect. The largest living specimen is purported to be the eater from Burundi named Gustave, it is believed to be more than 6.1 m (20 ft) long. Monster rare today, before the heavy hunting the 1940s and the 1950s, a larger population base and more extensive wetland habitats meant more monsters.
There is evidence of Nile crocodiles from cooler climates like the southern tip of Africa became smaller, and can reach lengths of only 4 m (13 ft). Dwarf Nile crocodiles also exist in Mali and in the Sahara Desert, which was only 2 to 3 m (6 feet 7 to 9 ft 10 in) long. Reduced their size is probably the result of less than ideal environmental conditions, not genetics.