It has a sparse covering of hair, existing almost entirely in the region of the lips, ears and tip of tail) and has many glands and tissue fat.
It must be constantly moist and secretes a reddish colored liquid, which serves as protection from dehydration.
This secretion led to the belief that hippos are able of "sweating blood". The upper and lower canines can reach 60 to 80 cm long and weigh over 3 kg. These always grow throughout the hippos life.
The incisors are long and are also facing forward in the lower jaw. These teeth are used in fights between rivals. In most battles, the winner is the animal that has the largest canines. In these battles, legs and neck are the most affected parts of the body.
Often, the animal dies as a direct result of injuries sustained in fights. The hippopotamus eyes, ears and nostrils are placed in order to stay above the surface when the animal moves through the water. The nostrils close when the animal submerges.
The hippos are sociable and gregarious animals. They live in groups of variable size, usually 10 to 30 individuals, but may gather in greater numbers.
The groups consist of one dominant male, several females and offspring. Solitary individuals are rare. Males dig furrows, which have up to four feet deep along the banks of rivers and lakes where they establish their territories.
These grooves are used for water to penetrate further inland, at the time of floods, thereby increasing the pasture area of its territory. Hippos spend most of the day on the water or close to it and just move to shore at night to graze. An adult can ingest more than 100 kg of vegetation in a single night and destroy almost the same quantity just by going over it.
They return to the river at dawn. They are particularly aggressive and may even be fatal to humans, when, on their return they encounter people along the water. The notoriety of these animals as one of the most dangerous animals in Africa is thus well justified. If the rivers dry up, the group moves to larger waterways and rivers.
The Hippo's droppings are extremely important for the balance of food chain in rivers and lakes in Africa, because they serve as fertilizer for algae growth, which in turn are eaten by fish.
Even for crocodiles, hippos are a fearsome opponent, with their strong canines and incisors, so crocodiles rarely dare to approach an adult animal. The young are, however, vulnerable to attack by a Nile crocodile in the water, and lions on land, but only if it is possible to elude the attention of its strong and protective mother. Hippopotamus can run at amazing speed of 30 km/h.
Hippopotamus - Diet
The hippos feed mainly of herbaceous. The vegetation is stripped away with their lips and chewed by the molars.
Hippopotamus - Reproduction
The mating, childbirth and nursing generally occur in water. Births can occur at any time of year, but they take place usually during the wet season. The gestation period is eight months, after which, the calf is born with 30 to 50 kg in weight, who is breastfed for six to eight months.
After the calf is weaned it does not leave the protection of the mother, so it is common to observe females accompanied by 2 to 4 cubs of different ages. Female hippos reach sexual maturity at 4 years of age and males at age 6 or later.
However, matings occur only between 7 and 15 years in the case of females, and between 6 and 13 years in the case of males.
Hippopotamus - Conservation status and main threats
Hippos are not considered globally threatened (by the International Union for Conservation of Nature) and, although it is mainly found in protected areas, there are still places where their numbers are large enough to cause crop damage. Is protected in most of its current distribution area.
About 2000 years, hippopotamus were found throughout Africa, wherever there was water with a temperature between 18 to 36 º C and food available. With the exception of tropical rain forests, they existed in the Nile Delta in South Africa, the Sahel and southern Sahara.
Since then it has been heavily hunted by farmers (due to damage caused to crops) and the trophy hunters and for the ivory, which is considered by some, better than that of the elephant, and to obtain meat for human consumption.
The species became extinct in North and South of Africa and much of the delta of the Nile river (in Egypt around 1816). Hippos can found in many large zoos, where he reproduces with relative ease. Hippopotamus are listed in the CITES Appendix II.
Species: H. amphibius