The Nile crocodile is one of the largest crocodilian species. This reptile is a highly adapted aquatic predator. Females of this species are noticeably smaller than males. The body is streamlined, the tail is long and sturdy, and the hind feet of the animal are webbed. The reptile has long and powerful jaws, which perfectly fit catching and holding the prey. Due to a special valve, found at the back of their throat, these crocodiles can move underwater with an open mouth, and grab and hold prey without ingesting water. The animal has a grey-olive body and a yellowish belly. Young crocodiles are identified by greenish or dark olive-brown coloration and black-colored cross-banding all over the body and tail. As the crocodile grows up, the banding on its body becomes fainter.
Nocturnality is an animal behavior characterized by being active during the night and sleeping during the day. The common adjective is "nocturnal",...
A carnivore meaning 'meat eater' is an organism that derives its energy and nutrient requirements from a diet consisting mainly or exclusively of a...
Scavengers are animals that consume dead organisms that have died from causes other than predation or have been killed by other predators. While sc...
Semiaquatic animals are those that are primarily or partly terrestrial but that spend a large amount of time swimming or otherwise occupied in wate...
An apex predator, also known as a top predator, is a predator at the top of a food chain and has no natural predators. These animals usually occup...
Precocial species are those in which the young are relatively mature and mobile from the moment of birth or hatching. Precocial species are normall...
Congregatory animals tend to gather in large numbers in specific areas as breeding colonies, for feeding, or for resting.
Oviparous animals are female animals that lay their eggs, with little or no other embryonic development within the mother. This is the reproductive...
Ambush predators are carnivorous animals that capture or trap prey by stealth, luring, or by (typically instinctive) strategies utilizing an elemen...
A burrow is a hole or tunnel excavated into the ground by an animal to create a space suitable for habitation, temporary refuge, or as a byproduct ...
Polygyny is a mating system in which one male lives and mates with multiple females but each female only mates with a single male.
Dangerous animals demonstrate aggression and a propensity to attack or harass people or other animals without provocation.
A dominance hierarchy (formerly and colloquially called a pecking order) is a type of social hierarchy that arises when members of animal social gr...
NoNot a migrant
Animals that do not make seasonal movements and stay in their native home ranges all year round are called not migrants or residents.
Aestivation is a state of animal dormancy, similar to hibernation, although taking place in the summer rather than the winter. Aestivation is chara...
The Nile crocodile is widely distributed across Sub-Saharan Africa. They most frequently occur in the central, eastern, and southern regions of Africa as well as Western Madagascar. Nile crocodiles can live in a broad range of habitat types, including small brackish streams, fast-flowing rivers, swamps, dams, and tidal lakes and estuaries. In East Africa, they are found mostly in rivers, lakes, marshes, and dams, favoring open, broad bodies of water over smaller ones. They are often found in waters adjacent to various open habitats such as savanna or even semi-desert but can also acclimate to well-wooded swamps, extensively wooded riparian zones, waterways of other woodlands, and the perimeter of forests. In Madagascar, the remnant population of Nile crocodiles has adapted to living within caves. Although not a regular sea-going species, the Nile crocodile possesses salt glands like all true crocodiles and may occasionally enter coastal and even marine waters.
Nile crocodiles are solitary animals. However, they can occasionally be seen feeding in small groups, consisting of several individuals. They usually use a special technique, enclosing an area of water in order to concentrate fish within it. Then, dominance hierarchies decide, in what order the members of the group will feed. These reptiles are mainly nocturnal. By day, the crocodiles typically sunbathe or cool off in the water if needed. Male crocodiles are highly territorial; they patrol and defend their territories, which often include a part of the shoreline, extending about 50 meters into the water. Nile crocodiles usually dive for a few minutes, before they come to the surface; however, when threatened, they are able to remain submerged for up to 30 minutes. Moreover, when completely inactive, these reptiles are capable of holding their breath for as long as 2 hours. They are exceptionally fast runners, and in general, these crocodiles have very quick reflexes, but, unfortunately, tire quickly.
Nile crocodiles are carnivores and scavengers. They feed upon a wide variety of animal species, including insects, amphibians, fish, and land mammals such as giraffes or Cape buffaloes. Newly hatched crocodiles usually start with insects, eventually going over to larger prey. Nile crocodiles also scavenge or steal kills from other predators, such as lions and leopards, and groups of Nile crocodiles may travel hundreds of meters from a waterway to feast on a carcass. They will also readily feed on dead hippopotamuses.
Nile crocodiles have a polygynous mating system, where one male mates with a number of females. Male crocodiles usually attract receptive females, making a wide variety of noises through bellowing, slapping their snouts in the water, or blowing water of out their noses. Meanwhile, larger males are typically more successful in finding mates. The nesting season in this species occurs in November-December. During this period, a female crocodile digs a nest, which is a hole in a riverbank or sandy river bed. Then, 25-80 eggs are laid and incubated for 80 - 90 days. When the hatching time approaches, the female opens the nest, carrying her offspring to the water. After a while, the young join a crèche of juveniles, which is looked after by females. The hatchlings can remain in this crèche for the first 2 years of their lives. Nile crocodiles become reproductively mature at 12-16 years old.
The primary threats to this species have to do with humans. Thus, the reptile attracts hunters for its skin, which is used in the production of high-quality leather. On the other hand, being large and dangerous predators, the Nile crocodiles face aggression from humans, who destruct their nests and frequently kill the crocodiles. Attempting to remove caught fish from fishing nets, these animals occasionally damage the nets, which leads to conflict between the crocodiles and fishermen. In Greater St Lucia Wetland Park in South Africa, the animals are threatened by the invasion of exotic plants that shade and supplant their nesting sites, cooling their eggs, which can potentially bring an all-female population.
Classified as Least Concern (LC) on the IUCN Red List, this reptile is currently not endangered. The overall estimated population of the Nile crocodile varies from 250,000 to 500,000 individuals.